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BOTANY  FOR  SECONDARY 
SCHOOLS 


THE  MACMILLAN  COMPANY 

NEW  YORK    •    BOSTON   •    CHICAGO 
ATLANTA   •    SAN    FRANCISCO 

MACMILLAN  &  CO.,  Limited 

LONDON  •  BOMBAY  •  CALCUTTA 
MELBOURNE 

THE  MACMILLAN  CO.  OF  CANADA,  Ltd. 

TORONTO 


1  "From  fragile  mushrooms,  delicate  water  -  weeds  and  pond  scums,  to  floating  leaves, 
soft  grasses,  coarse  weeds,  tall  bushes,  slender  climbers,  gigantic  trees  and 
hanging  moss."    See  Chapter  I. 


BOTANY  FOR 
SECONDARY  SCHOOLS 


A  GUIDE  TO  THE 

KNOWLEDGE  OF  THE  VEGETATION 

OF  THE  NEIGHBORHOOD 


-3 

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3— 

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4 

BY 

4- 

Li 

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BAILEY 

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&tto  gorfe 
THE   MACMILLAN  COMPANY 

LONDON :  MACMILLAN  &  CO.,  Ltd. 

1913 

All  rights  reserved 


Copyright  1900,  1907,  1913 
By  L.  H.  BAILEY 


New  edition  set  up  and  electrotyped  July,  1913 
Reprinted  October,  1913 


JKount  Pleasant  Pregg 

I.  Horace  McFarland  Company 


■  A< 


\0 


PARAGRAPHS  FOR  THE  TEACHER 

The  purpose  of  this  book  is  to  lead  the  pupil  to  an 
understanding  of  the  vegetation  of  his  neighborhood. 

There  are  four  general  subjects  in  the  book:  the 
nature  of  the  plant  itself;  the  relation  of  the  plant 
to  its  surroundings;  histological  studies;  determination 
of  the  kinds  of  plants.  From  the  pedagogical  point 
of  view,  the  third  is  the  least  important:  tho  writer 
has  inserted  it  because  so  many  schools  want  it.  Each 
of  the  subjects  is  practically  distinct,  so  that  the 
teacher  may  begin  where  he  will.  Few  schools  will 
desire  to  pursue  all  the  four  parts. 

The  notes  in  small  type  at  the  ends  of  the  chap- 
ters are  intended  as  suggestions  and  to  supply  infor- 
mation to  teachers:  they  are  not  necessarily  for  class 
use.  The  "Notes"  suggest  additional  experiments  and 
corollary  observations. 

***** 

The  schools  and  the  teachers  are  not  ready  for  the 
text-book  that  presents  the  subject  from  the  view- 
point of  botanical  science.  Perhaps  it  is  better  that 
the  secondary  schools  attempt  only  to  teach  plants. 

A  book  may  be  ideal  from  the  specialist's  point  of 
view,  and  yet  be  of  little  use  to  the  pupil  and  the 
school. 

Every  statement  in  an  elementary  text-book  has 
two  values, — the  teaching  value  and  the  scientific 
value.    An  elementary  text  exists  primarily  for  the 

7"7^X  ■        (V)  mOPfWTVnr 


VI         PARAGRAPHS  FOR  THE  TEACHER 

purpose  of  teaching;  and  good  teaching  results  in 
quickened  perception  rather  than  in  accumulation  of 
facts. 

The  pupil  should  come  at  first  to  the  study  of  plants 
and  animals  with  little  more  than  his  natural  and  native 
powers.  Study  with  the  compound  microscope  is  a 
specialization  to  be  made  when  the  pupil  has  had 
experience,  and  when  his  judgment  and  sense  of 
relationships  are  trained. 

One  of  the  first  essential  conceptions  to  the  study 
of  natural  history  is  the  fact  that  no  two  things  are 
alike.  This  leads  to  the  understanding  that  every 
animal  and  plant  contends  for  an  opportunity  to  live; 
and  this  is  the  central  fact  in  the  study  of  living  things. 
The  world  has  a  new  meaning  when  this  fact  is 
understood. 

The  ninety  and  nine  cannot  and  should  not  be 
botanists,  but  everyone  can  love  plants  and  nature. 
Every  person  is  interested  in  the  evident  things,  few 
in  the  abstruse  and  recondite.  Education  should  train 
persons  to  live,  rather  than  to  be  scientists. 

Now  and  then  a  pupil  develops  a  love  of  science 
for  science's  sake.  He  would  be  an  investigator.  He 
would  add  to  the  sum  of  human  knowledge.  He  should 
be  encouraged.  There  are  colleges  and  universities  in 
which  he  may  continue  his  studies. 

In  the  secondary  schools,  botany  should  be  taught 
for  the  purpose  of  bringing  the  pupil  closer  to  the 
things  with  which  he  lives,  of  widening  his  horizon, 
of  intensifying  his  hold  on  life.  It  should  begin  with 
familiar  plant  forms  and  phenomena.  It  should  be 
related  to  the  experiences  of  the  daily  life.  It  should 
not  be  taught  for  the  purpose  of  making  the  pupil 


PARAGRAPHS  FOR  THE  TEACHER         Vll 

a  specialist:  that  effort  should  be  retained  for  the  few 
who  develop  a  taste  for  special  knowledge.  It  is  often 
said  that  the  high-school  pupil  should  begin  the  study 
of  botany  with  the  lowest  and  simplest  forms  of  life. 
This  is  an  error.  The  microscope  is  not  an  introduc- 
tion to  nature.  It  is  said  that  the  physiology  of  plants 
can  be  best  understood  by  beginning  with  the  lower 
forms.  This  may  be  true:  but  technical  plant  physiol- 
ogy is  not  a  subject  for  the  beginner.  Other  subjects 
are  more  important. 

The  youth  is  by  nature  a  generalist.    He  should 
not  be  forced  to  be  a  specialist. 


A  great  difficulty  in  the  teaching  of  botany  is  to 
determine  what  are  the  most  profitable  topics  for  con- 
sideration. The  trouble  with  much  of  the  teaching  is 
that  it  attempts  to  go  too  far,  and  the  subjects  have 
no  connection  with  the  pupil's  experience. 

Good  botanical  teaching  for  the  young  is  replete 
with  human  interest.  It  is  connected  with  the  common 
associations. 

The  teacher  often  hesitates  to  teach  botany  because 
of  lack  of  technical  knowledge  of  the  subject.  This 
is  well;  but  technical  knowledge  of  the  subject  does 
not  make  a  good  teache..  Expert  specialists  are  so 
likely  to  go  into  mere  details  and  to  pursue  particu- 
lar subjects  so  far,  when  teaching  beginners,  as  to  miss 
the  leading  and  emphatic  points.  They  are  so  cogni- 
zant of  exceptions  to  every  rule  that  they  qualify  their 
statements  until  the  statements  have  no  force.  There 
are  other  ideals  than  those  of  mere  accuracy.  In  other 
words,   it  is  more  important  that  the  teacher  be  a 


Vlll  PARAGRAPHS    FOR    THE    TEACHER 

good  teacher  than  a  good  botanist.  One  may  be  so 
exact  that  his  words  mean  nothing.  But  being  a  good 
botanist  does  not  spoil  a  good  teacher;  and  the  ideal 
teacher  is  one  who  has  careful  knowledge  and  knows 
how  to  teach. 

An  imperfect  method  that  is  adapted  to  one's  use 
is  better  than  a  perfect  method  that  cannot  be  used. 
Some  school  laboratories  are  so  perfect  that  they  dis- 
courage the  pupil  in  making  inquiries  when  thrown 
on  his  own  resources.  Imperfect  equipment  often 
encourages  ingenuity  and  originality.  A  good  teacher 
is  better  than  all  the  laboratories  and  apparatus. 

Good  teaching  devolves  on  the  personality  and 
enthusiasm  of  the  teacher;  but  subject-matter  is  a 
prime  requisite.  The  teacher  should  know  more  than 
he  attempts  to  teach.  Every  teacher  should  have 
access  to  the  current  botanical  books.  The  school 
library  should  contain  these  books.  By  consulting  the 
new  books  the  teacher  keeps  abreast  of  the  latest 
opinion  and  points  of  view. 


When  beginning  to  teach  plants,  think  more  of 
the  pupil  than  of  botany.  The  pupil's  mind  and  sym- 
pathies are  to  be  expanded:  the  science  of  botany  is 
not  to  be  extended.  The  teacher  who  thinks  first  of 
his  subject  teaches  science;  he  who  thinks  first  of  his 
pupil  teaches  nature-study. 

Teach  first  the  things  nearest  to  hand.  When  the 
pupil  has  seen  the  common,  he  may  be  introduced  to 
the  rare  and  distant.  We  live  in  the  midst  of  common 
things. 

The  old  way  of  teaching  botany  was  to  teach  the 


PARAGRAPHS  FOR  THE  TEACHER         IX 

forms  and  the  names  of  plants.  It  is  now  proposed 
that  only  function  be  taught.  But  one  cannot  study 
function  intelligently  without  some  knowledge  of  plant 
forms  and  names.  He  must  know  the  language  of  the 
subject.  The  study  of  form  and  function  should  go 
together.  Correlate  what  a  plant  is  with  what  it  does. 
What  is  this  part?  What  is  its  office,  or  how  did  it 
come  to  be?  What  are  its  relations?  It  were  a  pity  to 
teach  phyllotaxy  without  teaching  light-relation:  it 
were  an  equal  pity  to  teach  light-relation  without 
teaching  phyllotaxy. 


Four  epochs  can  be  traced  in  the  teaching  of  ele- 
mentary botany:  (1)  The  effort  to  know  the  names  of 
plants  and  to  classify.  This  was  the  outgrowth  of  the 
earlier  aspect  of  plant  knowledge,  when  it  was  neces- 
sary to  make  an  inventory  of  the  things  in  the  world. 
(2)  The  desire  to  know  the  formal  names  of  the  parts 
of  plants.  This  was  an  outgrowth  of  the  study  of  gross 
morphology.  Botanies  came  to  be  dictionaries  of 
technical  terms.  (3)  The  effort  to  develop  the  powers 
of  independent  investigation.  This  was  largely  a  result 
of  the  German  laboratory  system,  which  developed  the 
trained  specialist  investigator.  It  emphasized  the 
value  of  the  compound  microscope  and  other  appa- 
ratus. This  method  is  of  the  greatest  service  to  botani- 
cal science  and  to  mankind,  but  its  introduction  into 
the  secondary  schools  is  usually  unfortunate.  (4)  The 
effort  to  know  the  plant  as  a  complete  organism  liv- 
ing its  own  life  in  a  natural  way.  In  the  beginning  of 
this  epoch  we  are  now  living. 


X         PARAGRAPHS  FOR  THE  TEACHER 

There  is  a  general  protest  against  the  teaching  of 
"big  names"  to  pupils;  but  the  pupil  does  not  object 
to  technical  terms  if  he  acquires  them  when  he  learns 
the  object  to  which  they  belong,  as  he  acquires  other 
language.  When  a  part  is  discovered,  the  name  becomes 
a  necessity,  and  is  not  easily  forgotten.  He  should  be 
taught  not  to  memorize  the  names.  The  "hard" 
words  of  today  are  the  familiar  words  of  tomorrow. 
There  are  no  words  in  this  book  harder  than  chrysan- 
themum, thermometer,  and  hippopotamus. 

The  book  should  be  a  guide  to  the  plant:  the  plant 
should  be  a  guide  to  the  book. 

Plants  should  not  be  personified  or  endowed  out- 
right with  motives;  but  figures  of  speech  and  para- 
bles may  often  be  employed  to  teach  a  lesson  or  to 
drive  home  a  point. 

Excite  the  pupil's  interest  rather  than  his  wonder. 

The  better  the  teacher,  the  less  he  will  confine  him- 
self to  the  questions  at  the  end  of  the  lesson. 

Botany  always  should  be  taught  by  the  "laboratory 
method:"  that  is,  the  pupil  should  work  out  the  sub- 
jects directly  from  the  specimens  themselves.  It  is 
easy,  however,  to  carry  the  laboratory  method  too 
far.  With  beginners,  it  is  rarely  good  teaching  merely 
to  set  a  young  pupil  a  task,  expecting  him  to  work 
it  out.  The  pupil  needs  suggestions,  help,  and  the 
enthusiasm  inspired  by  a  good  teacher. 

Specimens  mean  more  to  the  pupil  when  he  collects 
them. 

No  matter  how  commonplace  the  subject,  a  speci- 
men will  vivify  it  and  fix  it  in  the  pupil's  mind. 

A  living,  growing  plant  is  worth  a  score  of  herba- 
rium specimens. 


PARAGRAPHS  FOR  THE  TEACHER         XI 

Every  opportunity  should  be  taken  to  send  the 
pupils  to  the  fields  to  see  the  plants  naturally  as  they 
grow. 

Remember  that  garden  plants  and  field  crops  are 
as  "botanical"  and  as  well  worth  the  attention  of 
botanists  as  are  wild  plants. 


Many  persons  have  aided  in  the  making  of  this  book 
as  it  has  gone  through  its  various  editions.  In  this 
present  revision  the  author  has  had  the  help  of  Lewis 
Knudson,  Assistant  Professor  of  Plant  Physiology,  and 
acting  head  of  the  department,  in  the  New  York  State 
College  of  Agriculture  at  Cornell  University,  assisted 
by  M.  F.  Barrus,  Assistant  Professor  of  Plant  Pathology 
in  the  same  institution,  who  have  reviewed  the  work 
from  first  to  last  with  much  care. 

L.  H.  BAILEY. 

Ithaca,  New  York, 
May  20,   1913. 


CONTENTS 

PART  I 
The  Plant  Itself 

CHAPTER  PAGE 

I.   The  Plant  as  a  Whole 1 

II.   The  Root 7 

III.  The  Stem 13 

IV.  Propagation  by  Means  of  Roots  and  Stems    ...  18 
V.    How  the  Horticulturist  Propagates  Plants  by  Means 

of  Roots  and  Stems 23 

VI.   Food  Reservoirs 31 

VII.   Winter  Buds 36 

VIII.    Plants  and  Sunlight 42 

IX.   Struggle  for  Existence  amongst  the  Branches       .      .  52 

X.   Pruning 59 

XI.   The  Forms  of  Plants G4 

XII.   Water  and  Mineral  Nutrients. — Root  Action       .      .  69 

XIII.  Water  and   Mineral  Nutrients. — Action  above   the 

Roots 75 

XIV.  Food  Elaboration,  and  Respiration 82 

XV.    Dependent  Plants 90 

XVI.   Leaves  and  Foliage 95 

XVII.    Morphology,  or  the  Study  of  the  Forms  of  Plant 

Members 105 

XVIII.   How  Plants  Climb 112 

XIX.    Flower-Branches 118 

XX.   The  Parts  of  the  Flower 127 

XXI.    Fertilization  and  Pollination 133 

XXII.    Particular  Forms  of  FlowerB 143 

XXIII.   Fruits .155 

(xiii) 


XIV 


CONTENTS 


CHAPTER  PAGE 

XXIV.  Dispersal  of  Seeds 166 

XXV.  Germination 171 

XXVI.  Phenogams  and  Cryptogams 179 

XXVII.  Studies  in  Cryptogams 185 


PART  II 

The  Plant  in  Its  Relation  to  Environment 
and  to  Man 

XXVIII.   Where  Plants  Grow 205 

XXIX.    Contention  with  Physical  Environment     ....  212 

XXX.   Competition  with  Fellows 218 

XXXI.   Plant  Societies 228 

XXXII.   Variation  and  Its  Results 236 

XXXIII.  Weeds 241 

XXXIV.  Crops 249 

XXXV.   The  Forest 256 


PART  III 
Histology,  or  the  Minute  Structure  of  Plants 

XXXVI.   The  Cell 263 

XXXVII.   Contents  and  Products  of  Cells 270 

XXXVIII.   Tissues 278 

XXXIX.   Structure  of  Stems  and  Roots 285 

XL.   Structure  of  Leaves .     .  297 


PART  rv 
The  Kinds  of  Plants  (p.  307) 


BOTANY   FOR   SECONDARY  SCHOOLS 


PART  I— THE  PLANT  ITSELF 


CHAPTER   I 


THE   PLANT   AS   A   WHOLE 


1.  A  plant  is  a  living,  growing  thing.  It  partakes  of 
the  soil  and  air  and  sunshine.  It  propagates  its  kind  and 
covers  the  face  of  the  earth.  It  has  much  with  which  to 
contend.  It  makes  the  most  of  every  opportunity.  We 
shall  learn  its  parts,  how  it  lives,  and  how  it  responds. 

2.  The  Parts  of  a  Plant. — Our  familiar  plants  are  made 
up  of  several  distinct  parts.  The  most  prominent  of  these 
parts  are  root,  stem,  leaf,  flower,  fruit  and  seed.  (Fig.  2.) 
Familiar  plants  differ  wonderfully  in  size  and  shape, — from 
fragile  mushrooms,  delicate  water-weeds  and  pond-scums, 
to  floating  leaves,  soft  grasses, 

coarse  weeds,  tall  bushes, 
slender  climbers,  gigantic 
trees,  and  hanging  moss.  See 
frontispiece. 

3.  The  Stem  Part.— In 
most  of  the  familiar  plants 
there  is  a  main  central  part 
or  shaft  on  which  the  other 
or  secondary  parts  are  borne. 
This  main  part  is  the  plant 
axis.  Above  ground,  in  famil- 
iar   plants,    the    axis   bears 


IN  ■  > 


2.  The  parts  of  a  plant, — root,  stem, 
leaves,  pods  (or  fruit,  following  the 
flower) .    Bean. 


(1) 


2  THE    PLANT    AS    A    WHOLE 

the  branches,  leaves  and  flowers;  below  ground,  it  bears 
the  roots. 

4.  The  rigid  part  of  the  plant,  which  persists  over  win- 
ter and  which  is  left  after  leaves  and  flowers  are  fallen,  is 
the  framework  of  the  plant.  The  framework  is  composed 
of  both  root  and  stem.  When  the  plant  is  dead,  the  frame- 
work remains  for  a  time,  but  it  slowly  decays.  The  dry 
winter  stems  of  weeds  are  the  upper  part  of  the  framework  or 
skeleton  of  the  plant.  (Figs.  3,  4.)  The  framework  of  trees 
is  the  most  conspicuous  part  of  the  plant. 

5.  The  Root  Part. — The  root  bears  the  stem  at  its  apex, 
but  otherwise  it  normally  bears  only  root-branches.  The 
stem,  however,  bears  leaves,  flowers  and  fruits.  Those 
living  surfaces  of  the  plant  that  are  most  exposed  to  light 
are  green  or  highly  colored.  The  root  tends  to  grow  down- 
ward, but  the  stem  tends  to  grow  upward  toward  light. 
The  plant  is  anchored  or  fixed  in  the  soil  by  the  roots. 

6.  The  Foliage  Part. — The  leaves  precede  the  flowers 
in  point  of  time  or  in  the  life  of  the  plant,  although  the  flow- 
ers may  come  first  in  the  season  (note  that  peach  trees 
bloom  before  they  leaf).  The  flowers  always  precede  the 
fruits  and  seeds.  Many  plants  die  when  the  seeds  have 
matured.  The  whole  mass  of  leaves  of  any  plant  or  any 
branch  is  known  as  its  foliage. 

7.  The  Plant  Generation. — The  course  of  a  plant's 
life,  with  all  the  events  through  which  the  plant  naturally 
passes,  is  known  as  the  plant's  life-history.  The  life-history 
embraces  various  stages  or  epochs,  as  dormant  seed,  germi- 
nation, growth,  flowering,  fruiting.  Some  plants  run  their 
course  in  a  few  weeks  or  months,  and  some  live  for  centuries. 

8.  The  entire  life-period  of  a  plant  is  called  a  generation. 
It  is  the  whole  period  from  birth  to  normal  death,  without 
reference  to  the  various  stages  or  events  through  which 
it  passes. 

9.  A  generation  begins  with  the  young  seed,  not  with 


LENGTH     OF     LIFE 


germination.  It  ends  with  death — that  is,  when  no  life  is 
left  in  any  part  of  the  plant,  and  only  the  seed  or  spore 
remains  to  perpetuate  the  kind.  In  a  bulbous  plant,  as  a 
lily  or  an  onion,  the  generation  does  not  end  until  the  bulb 
dies,  even  though  the  top  is  dead. 

10.  When  the  generation  is  of  only  one  season's  duration, 
the  plant  is  said  to  be  annual. 

When  it  is  of  two  seasons,  it 
is  biennial.  Biennials  usually 
bloom  the  second  year.  When 
of  three  or  more  seasons,  the 
plant  is  perennial.  Examples 
of  annuals  are  pigweed,  bean, 
pea,  garden  sunflower,  maize; 
of  biennials,  evening  primrose, 
mullein,  teasel,  parsnip,  carrot; 
of  perennials,  dock,  meadow 
grass,  alfalfa,  cat-tail,  and  all 
shrubs  and  trees.  The  bien- 
nial and  perennial  weeds 
are  the  most  difficult  to 
eradicate. 

11.  Duration  of  the 
Plant  Body. — Plant  struc- 
tures that  are  more  or  less 
soft  and  that  die  at  the 
close  of  the  season  are  said 
to  be  herbaceous,  in  contradistinction  to  being  ligneous  or 
woody.  A  plant  that  is  herbaceous  to  the  ground  is  called 
an  herb;  but  an  herb  may  have  a  woody  or  perennial  root, 
in  which  case  it  is  called  an  herbaceous  perennial.  Annual 
plants  are  classed  as  herbs.  Examples  of  herbaceous  per- 
ennials are  buttercup,  bleeding-heart,  violet,  water-lily, 
many  grasses,  dock,  dandelion,  goldenrod,  asparagus, 
rhubarb,  many  wild  sunflowers  (Figs.  3,  4). 


THE     PLANT     AS     A    WHOLE 


12.  Many  herbaceous  perennials  have  short  generations. 
They  become  weak  with  one  or  two  seasons  of  flowering 
and  gradually  die  out.  Thus  common  red  clover  begins  to 
fail  after  the  second  year.  Gardeners  know  that  the  best 
bloom  of  hollyhock,  larkspur,  pink,  and  many  other 
plants,  is  secured  when  the  plants  are  only  two  or  three 
years  old. 

13.  Herbaceous  perennials  that  die  away  each  season 
to  bulbs,  corms  or  tubers,  are  sometimes  called  pseud-annuals 
(that   is,  false  annuals).     Of  such  are  lily,   crocus,  onion, 

>Vh.%^|*;,         .„  potato. 

14.  Plants    that 
are  normally  peren- 
nial   may    become 
annual  in  a  shorter- 
^  season    climate   by 
'¥■   being    killed    by 
frost,   rather    than 
ijs  by  dying  naturally 
at    the    end    of    a 
season    of    growth. 
Such    plants    are 
called  plur-annuals 
in  the  short-season 
region.     Many 
warm -region     per- 

5.  A  shrub  or  bush.     Dogwood  osier.  ennials     are        plur- 

annuals  when  grown  in  the  North,  but  they  are  treated  as 
true  annuals  because  they  ripen  sufficient  of  their  crop  the 
same  season  in  which  the  seeds  are  sown  to  make  them 
worth  cultivating,  as  tomato,  red  pepper,  castor-bean. 

15.  Woody  or  ligneous  plants  are  usually  longer  lived 
than  herbs.  Those  that  remain  low  and  produce  several 
or  many  similar  shoots  from  the  base  are  called  shrubs,  as 
lilac,  rose,  elder,  osier.    (Fig.  5.)    Low  and  thick  shrubs  are 


NO    TWO     PARTS    ARE     ALIKE 


U* 


K 


mm 

6.  A  Tree.     The  weeping  birch. 


-  r 


Plants  that  produce  one 
main  trunk  and  a  more  or  less 
elevated  head  are  trees.    (Fig.  6.) 

16.  Plants  are  Modified  by  the 
Conditions  in  Which  They  Grow. — 
In  most  plants,  the  size,  form 
and  general  appearance  vary  or 
change  with  the  conditions  in 
which  the  plant  grows.  That  is, 
there  is  no  uniform  or  necessary 
form  into  which  all  plants  shall 
grow.  No  two  plants  are  exactly 
alike.  Observe  plants  of  the  same 
kind  and  age,  and  see  how  they 
differ  or  vary.  The  farmer  and 
gardener  can  cause  plants  to  be 

large  or  small  of  their  kind,  by  changing  the  conditions  or 

circumstances  under  which  they  grow. 

17.  No  two  parts  of  the  same  plant  are  exactly  alike. 
No  two  parts  grow  in  the  same  conditions,  for  one  is  nearer 
the  main  stem,  one  nearer  the  light,  and  another  has  more 
room.  Try  to  find  two  leaves  or  two  branches  on  the  same 
plant  that  are  exactly  alike.    (Fig.  7.) 

18.  Every  plant  makes  an  effort  to  propagate  or  to  per- 
petuate its  kind;  and 
so  far  as  we  can  see, 
this  is  the  end  for 
which  the  plant  itself 
fives.  The  seed  or 
spore  is  the  final  pro- 
duct of  the  plant. 

19.  Every  plant, 
— and  every  part  of 
a  plant — undergoes 
vicissitudes.      Every 


6  THE     PLANT    AS    A    WHOLE 

plant  is  so  constituted  as  to  withstand  the  diverse  condi- 
tions of  the  circumstances  in  which  it  is  placed.  The  plant 
contends  for  place  in  which  to  grow,  and  for  air  and  light. 
Its  life  is  eventful.    Every  plant,  therefore,  has  a  history. 

Review. — Of  what  parts  is  a  plant  composed?  What  is  the  axis? 
What  parts  are  borne  on  the  stem?  On  the  root?  On  what  part  are  the 
mostly  highly  colored  parts  found?  What  direction  does  the  root  take? 
The  stem?  How  are  plants  anchored  in  the  earth?  In  what  order  do 
the  different  parts  appear?  What  is  meant  by  the  life-history?  What 
are  some  of  the  stages  or  events  in  the  life-history?  At  what  point 
does  a  generation  begin?  When  end?  By  what  means  does  the  next 
generation  begin?  What  is  an  annual?  Biennial?  Perennial?  Herb- 
aceous perennial?  Pseud-annual?  Shrub?  Bush?  Tree?  Give  three 
examples  of  each  of  these  classes,  not  mentioning  any  given  in  the  book. 
What  is  a  plur-annual?  Why  are  no  two  parts  or  plants  exactly 
alike?  What  is  the  final  effort  of  every  plant?  Why  is  the  life  of  a  plant- 
eventful? 

Note. — The  teacher  may  assign  each  pupil  to  one  plant  in  the 
school-yard,  field,  garden,  or  in  a  pot,  and  ask  him  to  bring  out  the 
points  in  the  lesson. 


%&> 


r£k  %&»'  -1: 


CHAPTER   II 

THE   ROOT 

20.  The  Root  System. — The  offices  of  the  root  are  to 
hold  the  plant  in  place,  and  to  absorb  water  and  mineral 
substances.  Not  all  roots,  however,  absorb  water  and  mineral 
nutrients. 

21.  The  entire  mass  of  roots  of  any  plant  is  called  its 
root  system.  The  root  system  may  be  annual,  biennial  or 
perennial,  herbaceous  or 
woody,  deep  or  shallow, 
large  or  small. 

22.  Kinds    of    Roots  — 
A    strong    leading    central 
root,   which    runs    directly 
downwards,    is    a    tap-root. 
The  side  or  spreading  roots  are  usually 
smaller.    Plants  that  have  such  a  root 
system    are    said    to    be    tap-rooted. 
Examples  are  red  clover,  beet,  turnip, 
radish,    burdock,    dandelion,    alfalfa. 
(Fig.  8.) 

23.  A  fibrous  root  system  is  one  that 
is  composed  of  many  nearly  equal,  slen- 
der branches.  The  greater  number  of 
plants  have  fibrous  roots.  Examples 
are  many  common  grasses,  wheat,  oats, 
corn,  and  most  trees.  The  bean  in 
Fig.  2  has  a  fibrous  root  system. 

24.  Shape  and  Extent  of  the  Root  System.— The  depth 
to  which  roots  extend  depends  on  the  kind  of  plant  and  the 

(7) 


i^£> 


Tap-root 
of  the 
dandelion. 


THE     ROOT 


nature  of  the  soil.    Of  most  plants  the  roots  extend  far  in  all 
directions   and   lie   comparatively   near   the   surface.     The 

roots  usually  radiate  from  a 
common  point  just  beneath 
the  surface  of  the  ground. 

25.  The  roots  may  be  of 
considerable  extent,  ramify- 
ing in  the  soil,  and  often 
extending  much  farther  in 
all  directions  than  the  spread 
of  the  top  of  the  plant. 
Roots  tend  to  spread  farther 
in  poor  soil  than  in  rich 
soil.  The  root  has  no  such 
definite  form  as  the  stem  has. 
Roots  are  usually  very 
crooked,  because  they  are 
constantly  turned  aside  by 
obstacles.  Examine  roots  in 
stony  or  gravelly  soil. 

26.  The  extent  of  root 
surface  is  usually  very  large, 
for  the  absorbing  roots  are 

fine  and  very  numerous.  An  ordinary  plant  of  Indian  corn 
may  have  a  total  length  of  root  (measured  as  if  the  roots 
were  placed  end  to  end)  of  hundreds 
of  feet.    (Fig.  9.) 

27.  The  finest  feeding  roots  are  in 
the  richest  soils.   It  is  commonly  stated 
that  they  are  attracted  by  the 
nutrients  of  the  soil.    This  is 
not   strictly  true.     The   roots 
may  grow  toward  a  supply  of  ^.^j^a 
water.    Notice  that  in  a  moist 

.,     ,  i  ,  ,  10.   The  bracing  buttresses  of 

sou  the  roots  are  short;  in  a  afield  pine. 


9.  The  abundant  roots  of  maize.  Note 
that  the  root  branches  are  much  more 
numerous  than  the  leaves. 


WHERE     ROOTS     GROW 


9 


dry  soil  they  are  usually  long.    Roots  of  the  willow  run  into 

wells  and  drains  and  into  the  margins  of  creeks  and  ponds. 

Roots  may  frequently  cause  trouble  by 

clogging  drain-pipes.     Grow  plants  in  a 

long,  narrow  box,  in  one  end  of  which 

the  earth  is  kept  very  dry  and  in  the  other 

moist:  observe  where  the  roots  grow. 

28.  The  absorbing  surface  of  the  roots 
is  near  their  ends.  As  the  roots  become 
old  and  hard,  they  serve  only  as  channels 
through  which  water  and  substances  in 

solution  pass,  and  as  hold- 
fasts or  supports  for  the 
plant.  The  root-hold  of  a 
plant  is  very  stong.  Slowly 
pull  upwards  on  some  plant, 
and  note  how  firmly  it  is 
anchored  in  the  earth.  With 
the  increase  in  diameter,  the 
upper  roots  often  protrude 
above  the  ground  and  be- 
come bracing  buttresses. 
These    buttresses    are    usu- 

of  the  radish,     ally    largest    in    trees    that 

always  have  been  exposed  to  strong  winds. 

(Fig.  10.) 

29.  The  Root-hairs.— The  larger  part 
of  the  water  and  mineral  nutrients  ab- 
sorbed by  the  root  is  taken  in  through  __ 
root-hairs.  (Fig.  11.)  These  are  very  del- 
icate prolonged  surface  cells  of  the 
roots.  They  are  borne  for  a  short  dis- 
tance just  back  of  the  tip  of  the  root. 

30.  The  root-hairs  are  very  small, 
often    invisible.    They,  and   the   young 


i | 


12.  Aerial  roots  of 
trumpet  creeper  or 
tecoma. 


10 


THE     ROOT 


roots,  are  usually  broken  off  when  the  plant  is  pulled  up. 
They  are  best  seen  when  seeds  are  germinated  between 
layers  of  dark  blotting-paper  or  flannel.  On  the  young 
roots,  they  will  be  seen  as  a  mould-like   or  gossamer-like 


13.   Drooping  aerial  roots  of  an  orchid. 


14.   Indian  corn,  showing  the 
aerial  roots. 


covering.    Root-hairs  soon  die:  they  do  not  grow  into  roots. 
New  hairs  form  as  the  root  grows. 

31.  Aerial  Roots. — Although  most  roots  grow  in  the 
earth,  there  are  some  that  grow  above  ground.  These  usually 
occur  on  climbing  plants,  the  roots  becoming  supports  or 
fulfilling  the  office  of  tendrils.  These  aerial  roots  usually 
grow  away  from  the  light,  and  therefore  enter  the  crevices 
and  dark  places  of  the  wall  or  tree  over  which  the  plant 
climbs.    The  trumpet-creeper  (Fig.  12),  true  or  English  ivy, 


ROOTS    ABOVE    GROUND  11 

and  poison  ivy  climb  by  means  of  roots.  The  roots  often 
remain  on  the  wall  or  other  support  after  the  plant  is  torn  off. 
32.  In  some  plants,  all  the  roots  are  aerial;  that  is,  the 
plant  grows  above  ground,  and  the  roots  absorb  water  from 
the  air  and  from  the  bark  of  the  tree  on  which  they  grow. 
Such  plants  are  known  as  epiphytes  or  air-plants  (Chapter 
XV).  The  most  familiar  examples  are  some  of  the  tropical 
orchids,  which  are  grown  in  glasshouses.    (Fig.  13.) 

33.   Some  plants  throw  out  aerial  roots  that  propagate 
the  plant  or  act  as  braces.    The  roots  of  Indian  corn  are 


15.   A  banyan  tree  in  India.    The  old  trunk  is  seen  (at  the  left),  together  with 
many  trunks  formed  from  the  aerial  roots. 

familiar.  (Fig.  14.)  Many  licus  trees,  as  the  banyan  of  India 
(Fig.  15),  send  out  roots  from  their  branches;  when  these 
roots  reach  the  ground  they  take  hold  and  become  great 
trunks,  thus  spreading  the  top  of  the  parent  tree  over  large 


12 


THE     ROOT 


areas.  The  mangrove  tree  (Fig.  16)  of  the  tropics  grows 
along  seashores  and  sends  down  roots  from  the  overhanging 
branches   into   the   shallow  water,   and  thereby  gradually 

marches  into  the  sea. 
The  tangled  mass  behind 
catches  the  drift,  and  soil 
is  formed. 

Review. — What  is  the 
root  for?  What  is  a  root 
system?  Define  tap  -  root. 
Fibrous  root.  What  deter- 
mines how  deep  the  root 
may  go?  How  far  does  the 
root  spread?  Explain  what 
form  the  root  system  may 
assume;  also  what  extent. 
Where  is  the  greatest  number 
of  fine  roots  found?  Where 
is  the  absorbing  surface  of 
roots?  Of  what  use  to  the 
plant  are  the  old  woody  roots? 
What  are  root-hairs?  What 
do  they  do  and  what  becomes 
of  them?  What  are  aerial 
roots?  Where  found?  What  are  epiphytes,  and  where  do  their  roots 
grow?  What  are  brace  roots?  How  do  the  banyan  and  mangrove  spread 
(aside  from  seeds)  ? 

Note. — The  pupil  should  see  the  root-hairs.  A  week  before  this 
lesson  is  studied,  the  pupil  should  place  seeds  of  radish,  turnip  or  cab- 
bage between  folds  of  thick  cloth  or  blotting-paper.  Keep  the  cloth  or 
paper  moist  and  warm.  The  hairs  show  best  against  a  dark  back- 
ground. In  some  of  the  blotting-papers,  sprinkle  sand:  observe  how 
the  root-hairs  cling  to  the  grains  (compare  Chapter  XII). 

The  pupil  also  should  study  the  root-hold  of  a  plant.  Let  him  care- 
fully pull  up  a  plant.  If  a  plant  grows  alongside  a  fence  or  other  rigid 
object,  he  may  test  the  root-hold  by  securing  a  string  to  the  plant, 
letting  the  string  hang  over  the  fence  and  then  adding  weights  to  the 
string.  Will  a  stake  of  similar  size  to  the  plant  and  extending  no  deeper 
in  the  ground,  have  such  firm  hold  on  the  soil? 


Mangroves  marching  into  the  sea. 


CHAPTER  III 


THE    STEM 


?Mk 


34.  The  Stem  System.— The  stem  of  a  plant  is  the 
part  that  bears  the  buds,  leaves,  flowers  and  fruits.  Its  office 
is  to  hold  up  these  parts  to  the  light  and  air;  and  through 
its  tissues  the  various  food-materials  and  nutrients  in  solu- 
tion in  water  are  distributed 
to  the  parts  of  the  plant. 

35.  The  entire  mass  or  fabric 
of  stems  of  any  plant  is  called 
its  stem  system.  (Figs.  4,  17.) 
The  stem  system  may  be  her- 
baceous or  woody,  annual,  bien- 
nial, or  perennial;  and  it  may 
assume  many  different  sizes  and 
shapes.    (Paragraphs  11  to  13.) 

36.  Stems  are  of  many  forms. 
The  general  way  in  which  a 
plant  grows  is  called  its  habit. 
The  habit  is  the  appearance  or 

looks.  Its  habit  may  be  open  or  loose,  dense,  straight, 
crooked,  compact,  straggling,  climbing,  erect,  weak,,  strong, 
and  the  like.  The  roots  and  leaves  are  the  important  func- 
tional or  working  parts  :  the  stem  merely  connects  them, 
and  its  form  is  exceedingly  variable. 

37.  Kinds  of  Stems. — The  stem  may  be  so  short  as  to 
be  scarcely  distinguishable.  In  such  cases  the  crown  of  the 
plant — that  part  just  at  the  surface  of  the  ground — bears 
the  leaves  and  flowers;  but  this  crown  is  really  a  very  short 
stem.  The  dandelion  (Fig.  8)  is  an  example.  Such  plants 
(13) 


17.     Stem  system  of  an  apple  tree. 
Deliquescent  trunk. 


14 


THE     STEM 


18.   A  trailing  plant  (Abronia,  grown  in  flower-gardens). 


are  often  said  to  be  stemless,  however,  in  order  to  distin- 
guish  them   from   plants   that   have   long   or   conspicuous 
stems.    These  so-called  stemless  plants  die  to  the  ground 
every  year. 
...  38.  Stems  are  erect  when  they  grow 

j.J%  straight  up.  (Figs.  3,  9.)  They  are 
trailing  or  creeping  when  they  run 
along  on  the  ground.  (Fig.  18.)  They 
are  decumbent  when  they  lop  over  to 
the  ground. 
They  are  ascend- 
ing when  they 
lie  mostly  or  in 
part  on  the 
ground  but  stand 
more  or  less  up- 
right at  their 
ends.  They  are  climbing  when  they  cling  to  other  rising 
objects  for  support.    (Fig.  12.) 

39.  Trees  in  which  the  main  trunk  or  the  "leader" 
continues  to  grow  from  its  tip  are  said  to  be  excurrent  in 
growth.  The  branches  are  borne  along 
the  sides  of  the  trunk,  as  in  common 
pines  (Fig.  19)  and  spruces.  Excurrent 
means  "running  out"  or  "running  up." 

40.  Trees  in  which  the  main  trunk 
does  not  continue  are  said  to  be  deliques 
cent.  The  branches  arise  from  one  com- 
mon point  or  from  each  other.  The  stem 
is  lost  in  the  branches.  The  apple  tree 
(Fig.  17),  maple,  elm,  oak,  are  familiar 
examples.  Deliquescent  means  "dissolv- 
ing" or  "melting  away." 

41.  Each  kind  of  plant  has  its  own 
peculiar   habit   or  direction   of  growth. 


KINDS    OF    STEMS 


15 


Spruces  always  grow  to  a  single  stem 
or  trunk,  pear  trees  are  always  deli- 
quescent, morning-glories  are  always 
climbing,  strawberries  are  always 
creeping.  We  do  not  know  why  each 
plant  has  its  own  habit;  but  the  habit 
is  in  some  way  associated  with  the 
plant's  genealogy  or  with  the  way  in 
which  it  has  been  obliged  to  live. 

il#  42.  The    stem 

may  be  simple  or 
branched.  (Figs.  20, 
21.)  A  simple  stem 
usually  grows  from 
the   terminal  bud, 


20.  Simple  stems  of  sorghum. 

and  side  branches  either  do  not  start,  or, 
if  they  start,  they  soon  perish.  Mul- 
leins are  usually  simple.  So  are 
palms. 

43.  Branched  stems  may  be  of 
very  different  habit  and  shape. 
Some  stem  systems  are  narrow  and 
erect:  these  are  said  to  be  strict. 
Others  are  diffuse,  open,  branchy, 
twiggy. 

44.  Stems  vs.  Roots. — Roots 
sometimes  grow  above  ground  (31- 
33) ;  so,  also,  stems  sometimes  grow 
underground,  and  they  are  then 
known  as  subterranean  stems,  rhi- 
zomes, or  rootstocks.    (Figs.  22,  23.) 

45.  Stems  normally  bear  leaves 
and  buds,  and  thereby  are  they  dis- 
tinguished from  roots.  The  leaves, 
however,  may  be  reduced  to  mere 


16 


THE    STEM 


scales,  and  the  buds  beneath  them  may  be 
scarcely  visible.  Thus  the  "eyes"  on  an  Irish 
potato  are  cavities  with  a  bud  or  buds  at  the 
bottom.  (Fig.  24.)  Sweet  potatoes  have  no 
evident  "eyes"  when  first  dug  (but  they  may 
develop  buds  before  the  next  growing  season). 
The  Irish  potato  is  a  stem;  the  sweet  potato 
is  an  enlarged  root. 

46.  How  Stems  Elongate. — Roots  elongate 
by  growing  near  the  tip.  Stems  elongate  by 
22.  wintergreen,  growing  more  or  less  throughout  the  young  or 
showing  rootstock.  g()ft  part  or  «ketween  joints."   But  any  part 

of     the     stem     soon 

reaches    a    limit    be- 
yond which  it  cannot 

grow,     or    becomes 

"fixed;"  and  the  new 

parts  beyond  elongate 

until  they,  too,  become 

rigid.   When  a  part  of  the  stem  once  becomes  fixed  or  hard, 
it  never  increases   in  length: 
that   is,  the  trunk  or  woody 
parts    never    grow    longer    or 
jjl  j  higher;    branches  do  not   be- 

'  A  come  farther  apart  or  higher 

from  the  ground. 

47.  The  different  regions  of 
growth  in  stems  and  roots 
may  be  observed  in  seedling 
plants.  Place  seeds  of  radish 
or  cabbage  between  layers  of 
blotting-paper  or  thick  cloth. 
Keep  them  damp  and  warm. 
When  the  stem  and  root  have 
grown  an  inch  and  a  half  long 


23.   Rhizome  of  a  wild  sunflower. 


V^pF 


24.  Potato.  Stems  (where?) ,  fine 
roots,  and  rootstocks. 


STEM    VS.    ROOT 


17 


each,  with  waterproof  ink  mark  spaces  exactly  one-quarter 
inch  apart.  Keep  the  plantlets  moist  for  a  clay  or  two,  and 
it  will  be  found  that  on  the  stem  some  or  all  of  the  marks 
are  more  than  one-quarter  inch  apart;  on  the  root  the 
marks  have  not  separated.  The  root  has  grown 
beyond  the  last  apical  mark.    (Figs.  25,  26.) 

Review. — What  is  the  stem  system?    What  does 
the  stem  do?    How  long  may  the  stem  persist?  Whal 
is  meant  by  the  habit  of  a  plant?    Name  some  kinds 
of   habit.     What  are  so-called  stemless  plants?    What 
is  the  crown?    What  becomes  of  the  tops  of  stemless 
plants?   What  are  erect,  trailing,  decumbent,  ascending, 
climbing  stems?     What   are   excurrent  trunks?     Deli- 
quescent?    What  is  a  simple  stem?     What  are  strict 
stems?    What  are  subterranean  stems?   How  are  sterna 
distinguished     from 
roots?   What  is  the  dif- 
ference   in    mode    of 
growth    between    stems 
and  roots? 

Note. — T  h  e  pupil 
s  h  o  u  1  d  make  marks 
with  waterproof  ink  (as 
Higgins'  ink  or  indelible 
marking  ink)  on  any 
soft  growing  stems  —  as 
geranium,  fuchsia,  grass, 
the  twigs  of  trees.  Note 
that  the  separation  of 
the  marks  is  most  evi- 
dent on  the  youngest 
shoots. 

The  pupil  should  observe  the  fact  that  a  stem  of  a  plant  has  wonder- 
ful strength.  Compare  the  proportionate  height,  diameter  ami  weight 
of  a  grass  stem  with  those  of  the  slenderest  tower  or  steeple.  Which 
has  the  greater  Strength?  Which  the  greater  height'.'  Which  will  with- 
stand the  most  wind?  Note  that  the  grass  stem  will  regain  its  position 
even  if  its  top  is  bent  to  the  ground.  Split  a  cornstalk  and  observe  how 
the  joints  are  tied  together  and  braced  with  fibers.  Note  how  plants 
are  weighted  down  after  a  heavy  rain. 
B 


25,.   The  markiiiK  of 
the  stem  and  root. 


20.   The  result. 


CHAPTER  IV 

PROPAGATION  BY  MEANS  OF  ROOTS  AND  STEMS 

48.  The  primary  function  of  roots  and  stems  is  to  support 
and  maintain  the  plant;  but  these  parts  may  also  serve  to 
propagate  the  plant,  or  to  produce  new  individuals. 

49.  Propagation  by  Means  of  Rhi- 
zomes.— One  function  served  by  subter- 
ranean stems  or  rhizomes  (rootstocks)  is 
to  propagate  the  species.  Each  stem  has  a 
bud  at  its  end,  and  from  this  bud  a  shoot 
arises.  By  the  dying  away  of  the  older 
part  of  the  rhizome,  this  shoot  becomes 
a  separate  plant,  although  the  rhizome 
maintains  its  connection  for  years  in  some 
plants.  Shoots  may  also  arise  from  the 
intermediate  or  lateral  buds,  but  the 
strongest  shoots  usually  arise  from  the  end 
or  near  the  end  of  the  rhizome.   (Fig.  23.) 

50.  Each  successive  plant  is  farther 
removed  from  the  original  plant  or  the 
starting-point  of  the  colony.  Thus  the 
colony  or  "patch"  grows  larger.  Familiar 
examples  are  the  spreading  patches  of 
mandrakes  or  may-apples,  quack-grass 
(Fig.  27),  Solomon's  seal,  lily-of-the-valley, 
ferns.      Cannas    propagate    by   means    of 

rhizomes;  so  does  ginger,  and 
the  "roots"  can  be  purchased 
at  the   drug -store.    Fig.  28 

27.  Quack-grass  or  couch-grass.     Point  .,,  ,t  ,        e 

out  the  rootstock.  illustrates    the    spread   of  a 

(18) 


SPREADING     BY     MEANS     OF    ROOTSTOCKS 


19 


28.  Creeping  rhizomes  of  wild  sunflower 


colony  of  wild  sunflower.  On  the  right 
the  rhizomes  have  died  away:  note  the 
frayed  ends.  On  the  left,  the  strong  up- 
turned buds  show  where  the  shoots  will 
arise  next  spring.  The  old  stems  in  the 
middle  show  where  the  buds  stood  at  the 
close  of  the  last  season.  Fig.  23  shows  one 
of  the  terminal  buds. 

51.  When  rhizomes  are  cut  in  pieces, 

each    piece   having   at   least  one  bud  or 

"eye,"  the  pieces  may  grow  when  planted. 

A    familiar    example    is    the   practice   of 

dividing  tubers  of  potato.   A  severed  piece 

of  plant  designed  to  be  used 

to  propagate  the  plant  is 

a  cutting.   See  Fig.  29. 

52.  Cuttings     of     rhi- 
zomes   are    often    made 


undesignedly  or  accidentally  when  land  is  cultivated.    The 
cultivator  or  har- 


row  breaks  u  p 
the  rhizomes  of 
quack-grass,  Can- 
ada-thistle, toad- 
flax, and  other 
weeds,  and  scat 
ters  them  over 
the  field. 

53.  Propa- 
gation by 
Means  of 
Roots . — 
Roots  some- 
times develop 
buds      and 


29.   Cuttings  of  canna  rhizome. 


20      PROPAGATION  BY  MEANS  OF  ROOTS  AND  STEMS 

throw  up  shoots  or  new  plants.  Severed  roots  often  grow. 
Blackberries,  raspberries,  and  many  plums  and  cherries, 
throw  up  shoots  or  "suckers"  from  the  roots;  and  this 
propensity  is  usually  increased  when  the  roots  are  broken, 
as  by  a  plow.  Broken  roots  of  apples  often  sprout.  Plants 
may  propagate  by  means  of  root-cuttings. 

54.  Occasional  Buds.— The  buds  that  appear  on  roots 
are  unusual  or  abnormal, — they  occur  only  occasionally  and 
in  no  definite  order.  Buds  appearing  in  unusual  places  on 
any  part  of  the  plant  are  called  adventitious  buds.  Such  are 
the  buds  that  arise  when  a  large  limb  is  cut  off,  and  from 
which  suckers  or  watersprouts  arise,  as  on  the  apple  tree. 

55.  Layers. — Roots  sometimes 
arise  from  aerial  stems  that  are 
partially  buried.  If  a  branch 
1yjpJ$  touches  the  ground  and  takes 
root,  it  is  called  a  layer.  Gar- 
deners often  bend  a  limb  to  the 
ground  and  cover  it  for  a  short 
distance,  and  when  roots  have 
-A^-  formed  on  the  covered  part,  the 

-$&.  branch  is  severed  from  its  parent 

30.  a  layer  of  dewberry.  The  new      and    an    independent    plant    is 

Plant  has  arisen  at  the  left.  secured.     See  Fig.  30. 

56.  There  are  several  kinds  of  layers:  a  creeper,  when  a 
trailing  shoot  takes  root  throughout  its  entire  length;  a 
runner,  when  the  shoot  trails  on  the  ground  and  takes  root 
at  the  joints,  as  the  strawberry;  a  stolon,  when  a  more  or  less 
strong  shoot  bends  over  and  takes  root,  as  the  black  rasp- 
berry or  the  dewberry  (Fig.  30) ;  an  offset,  when  a  few  very 
strong  plants  form  close  about  the  base  of  the  parent,  par- 
ticularly in  succulent  or  bulbous  plants,  as  house-leek 
(old-hen-and-chickens)  and  some  lilies.  The  rooting  branches 
of  the  banyan  and  mangrove  (Figs.  15,  16)  may  be  likened 
to  layers. 


BUD-PKOPA<;.ATIOX 


21 


31.  Bulblet  of 
tiger  lily. 


57.  Natural  Cuttings. — Sometimes  cuttings  occur  with- 
out the  aid  of  man.  Some  kinds  of  willows  shed  their  twigs, 
or  the  storms  break  them  off:  many  of  these  twigs  take 
root  in  the  moist  earth  where  willows  grow,  and 
they  are  often  carried  down  the  streams  and  are 
washed  along  the  shores  of  lakes.  Observe  the  wil- 
lows along  a  brook,  and  determine  whether  any  of 
them  may  have  come  down  the  stream. 

58.  Propagation  by  Means  of  Leaves. — 
Even  leaves  may  take  root  and  give  rise  to 
new  plants.  There  are  examples  in  warm 
countries.  The  lake-cress  of  northern  streams 
*also  propagates  in  this  way:  the  leaves  with 
little  plants  attached  may  often  be  seen  float- 
ing down  stream.  Gardeners  propagate  some 
kinds  of  begonias  by  means  of  leaf -cutting; 
also  gloxinias  and  bryophyllums.     (Paragraph  69.) 

59.  Propagation  by  Means  of 
Buds. — Buds  often  become  detached 
and  propagate  the  plant.  Familiar 
examples  are  the  bulblets  of  tiger 
lilies,  borne  amongst  the  foliage;  for 
all  bulblets  and  bulbs  are  only 
special  kinds  of  buds.  Fig.  31. 
Some  water  plants  make  heavy 
winter  buds,  which  become  de- 
tached on  the  approach  of  cold 
weather  and  sink  to  the  bottom. 
In  spring,  they  give  rise  to  new 
plants. 

60.  Grafts. — Sometimes  a  plant 
may  unite  with  another  plant.  A 
branch  or  a  trunk  may  lie  against 
another  plant  of  the  same  kind,  or  of 
a  very  closely  related  kind,  and  grow 


22       PROPAGATION  BY  MEANS  OF  ROOTS  AND  STEMS 

fast  to  it;  and  if  its  original  trunk  die  away,  the  part  will 
be  growing  on  an  alien  root.  A  branch  that  grows  fast 
to  a  branch  of  another  plant,  the  wood  of  the  two  knitting 
together,  is  called  a  graft.  (Fig.  32.)  It  is  necessary  to  dis- 
tinguish between  a  graft  and  a  parasite:  a  parasite  preys 
upon  another  plant,  robbing  it  of  its  food,  but  a  graft  becomes 
an  integral  part  of  the  stock  on  which  it  grows,  and  does 
its  full  work  in  elaborating  food  for  itself  and  for  the  stock. 

Review. — What  are  primary  and  secondary  functions  of  roots  and 
stems?  What  are  the  functions  of  rhizomes?  How  does  propagation 
by  rhizomes  proceed?  Why  does  the  colony  spread?  Name  some  plants 
that  propagate  by  means  of  rhizomes.  What  is  a  cutting?  May  cuttings 
be  made  of  rhizomes?  How  are  rhizomatous  weeds  often  spread? 
Name  some  of  them.  How  do  roots  serve  to  propagate  the  plant?  Name 
instances.  What  are  adventitious  buds?  What  is  a  layer?  Define  some 
of  the  kinds  of  layers, — runner,  creeper,  stolon,  offset.  Explain  how 
cuttings  may  occur  without  the  aid  of  man.  How  may  leaves  serve 
to  propagate  the  plant?  Explain  how  plants  propagate  themselves  by 
means  of  detachable  buds.  What  is  a  graft?  How  may  grafting  take 
place  without  the  aid  of  man? 

Note. — If  there  is  an  accessible  "patch"  of  toad-flax,  Canada 
thistle,  may-apple,  or  other  perennial  plant,  the  pupil  should  determine 
by  what  means  it  enlarges  from  year  to  year.  "Patches"  are  always 
instructive  when  considered  with  reference  to  propagation  and  dis- 
semination. 


CHAPTER  V 


HOW   THE   HORTICULTURIST   PROPAGATES   PLANTS   BY 
MEANS    OF   ROOTS   AND    STEMS 

61.  Cuttings  in  General. — A  bit  of  plant  stuck  into  the 
ground  stands  a  chance  of  growing;  and  this  bit  is  a  cutting. 
(Compare  51.)  Not  all  plants  can  be  propagated  by  the  same 
kind  of  cutting.  The  means  is  determined  by  experiment  or 
experience.  In  some  cases  the  part  to  be  used  and  the  con- 
ditions necessary  for  growing  the  cutting  have  not  been  dis- 
covered, and  we  say  that  the  plant  is  not  propagated  by 
cuttings.  It  is  probable  that  some  plants  cannot  be  grown 
from  cuttings,  even  under  the  greatest  skill. 

62.  Most  plants  propagate  from  cuttings  made  of  the 
soft  or  growing  parts  (called  "wood"  by  gardeners),  of  which 
the  "slips"  of  geranium  and  coleus  are  examples.  Others 
grow  equally  well  from  cuttings  of  the  hard  or  mature 
parts  or  wood,  as  currant  and  grape;  and  in  some  instances 
this  mature  wood  may  be  of  roots,  as  in  the  blackberry. 
Pupils  should  make  cuttings  now  and  then.    If  they  can 


do  nothing  more,  they  can  make  cuttings  of  potato 
farmer  does ;  and  they  can  plant  them  in  a     ^ 


as  th 


box  in  the  window. 

63.  The  Softwood  Cutting.— The  soft- 
wood cutting  is  made  from  tissue  that  is 
still  growing,  or  at  least  from  that  which 
is  not  dormant.  It  comprises  one  or  two 
joints,  with  a  leaf  attached.  (Figs.  33, 
34,  35.)  It  must  not  be  allowed  to  wilt. 
Therefore,  it  must  be  protected  from 
direct  sunlight  and  dry  air  until  it  is  well 
(23) 


33.  Geranium  cutting. 


24 


ARTIFICIAL     PROPAGATION 


established  in  the  earth;  and  if  it  has  many  leaves,  some  of 
them  should  be  removed,  or  at  least  cut  in  two,  to  reduce 
the  evaporating  surface.  Most  of  the  common  window-plants 

may  be  propagated 
easily  by  means  of 
softwood  cuttings 
or  slips. 

64.  For  most 
plants,  the  proper 
age  or  maturity  of 
wood  for  the  making  of  cuttings  may  be 
determined  by  giving  the  twig  a  quick 
bend :  if  it  snaps  and  hangs  by  the  bark,  it 
is  in  proper  condition;  if  it  bends  without 
breaking,  it  is  too  young  and  soft  or  too  old;  if  it  splinters, 
it  is  too  old  and  woody.  The  tips  of  strong  upright  shoots 
usually  make  the  best  cuttings.  Preferably,  each  cutting 
should  have  a  joint  or  node  near  its  base;  and  if  the  inter- 
nodes  (or  spaces  between  joints)  are  very  short,  it  may 
comprise  two  or  three  joints. 

65.  The  stem  of  the  cutting  is  inserted  one-third  or  more 
its  length  in  clean  sand  or  gravel,  and  the  earth  is  pressed 
firmly  about  it.    A  newspaper  may  be  laid  over  the  bed  to 


34.  Carnation 
cutting. 


36.  Cutting-bed,  showing  carnations  and  rosea. 


*•***&. 


MAKING    CUTTINGS 


25 


37.  Verbena  cutting  ready 
for  transplanting. 


exclude  the  light — if  the  sun  strikes  it — and  to  prevent 
too  rapid  evaporation.  The  soil  should  be  moist  clear 
through,  not  on  top  only. 

66.  Loose  sandy  or  gravelly  soil  is 
used.  Mason's  sand  is  good  earth  in 
which  to  start  most  cuttings;  or  fine 
gravel — sifted  of  most  of  its  earthy 
matter — may  be  used.  Soils  that  con- 
tain much  decaying  organic  matter  are 
avoided,  for  these  soils  are  breeding- 
places  of  fungi,  which  attack  the  soft 
cutting  and  cause  it  to  "damp  off,"  or 
die  at  or  near  the  surface  of  the  ground.  If  the  cuttings  are 
to  be  grown  in  a  window,  put  three  or  four  inches  of  the 
earth  in  a  shallow  box  or  a  pan.  A  soap  box  cut  in  two 
lengthwise,  so  that  it  makes  a  box  four  or  five  inches  deep 
— like  a  gardener's  flat — is  excellent.  A  cutting-bed  may 
be  made  on  a  greenhouse  bench  or  in  a  good  shaded  window, 
as  in  Fig.  36.  Cuttings  of 
common  plants,  as  gera- 
nium, coleus,  fuchsia,  carna- 
tion, are  kept  at  a  living- 
room  temperature.  As  long 
as  the  cuttings  look  bright 
and  green,  they  are  in  good 
condition.  It  may  be  a 
month  before  roots  form. 
When  roots  have  formed, 
the  plants  begin  to  make 
new  leaves  at  the  tip.  Then 
they  may  be  transplanted 
into  other  boxes  or  into 
pots.  The  verbena  in  Fig. 
37  is  just  ready  for  trans-         as.  ow  geraniun 

,       , .  make  it  I  brow  oul  a 

planting.  un(:>  oan  |,e  m.ul(._ 


26 


ARTIFICIAL     PROPAGATION 


67.  It  is  not  always  easy  to  find  growing  shoots  from 
which  to  make  the  cuttings.  The  best  practice,  in  that 
case,  is  to  cut  back  an  old  plant,  then  keep  it  warm  and  well 
watered,  and  thereby  force  it  to  throw  out  new  shoots.  The 
old  geranium  plant  from  the  window-garden,  or  the  one 
taken  up  from  the  lawn  bed,  may  be  treated  this  way. 
See  Fig.  38.  The  best  plants  of  geranium  and  coleus  and 
most  window-plants  are  those  that  are  not  more  than  one 

year  old.  The  ge- 
ranium and  fuchsia 
cuttings  that  are 
made  in  January, 
February,  o  r 
March  will  give 
compact  blooming 
plants  for  the  next 
winter;  and  there- 
after new  ones 
take  their  places. 
(Fig.  39.) 

68.  The  Hard- 
wood Cutting. — 
Best  results  are 
secured    when    the 

39.  Early  winter  geranium,  from  a  spring  cutting.  cuttings     are    ma(Je 

in  the  fall  and  then  buried  until  spring  in  sand  in  the  cellar. 
These  cuttings  are  usually  6  to  10  inches  long.  They  are  not 
idle  while  they  rest.  The  lower  end  calluses  or  heals,  and 
the  roots  form  more  readily  when  the  cutting  is  planted  in 
the  spring.  But  if  the  proper  season  has  passed,  take  cut- 
tings at  any  time  in  winter,  plant  them  in  a  deep  box  in  the 
window,  and  watch.  They  will  need  no  shading  or  special 
care.  Grape,  currant,  willow  and  poplar  readily  take  root 
from  the  hardwood.  Fig.  40  shows  a  currant  cutting.  It  has 
only  one  bud  above  the  ground. 


(T'TTIXCS     AM)     CRAFTS 


27 


40.  Currant  cutting. 


69.  Cuttings  of  Leaves. — Some  plants 
arc  regularly  propagated  by  leaf-cuttings. 
^rr  paragraph  58.  Begonias  of  the  "foliage" 
kinds  are  the  most  frequent  examples. 
Sometimes  the  leaf  is  cut  to  wedge-shaped 
parts,  each  part  with  a  midrib  and  a  bit  of 
the  leaf -stalk;  from  the  point  which  is  put 
in  the  earth  a  new  plant  arises,  as  shown 
in  Fig.  41.  Gardeners  often  cut  the  begonia 
leaf  across  and  set  the  severed  edge  in  the 
earth;  sometimes  they  lay  the  leaf  flat  on 
the  earth  and  peg  it  down  at  intervals. 
The  leaf  should  be  nearly  or  quite  mature, 
but  still  full  of  vigor. 

70.  The  Graft. — When  the  cutting  is 
inserted  in  a  plant  rather  than  in  the  soil, 
we  have  a  graft;  and  the  graft  may  grow. 
In  this  case  the  cutting  grows  fast  to  the 
other    plant,    and 


the  two  become 
one.  When  the  cutting  is  inserted 
in  a  plant,  it  is  no  longer  called  a 
cutting,  but  a  cion;  and  the  plant 
in  which  it  is  inserted  is  called  the 
stock.  Fruit  trees  are  grafted  in 
order  that  a  certain  variety  or  kind 
may  be  perpetuated. 

71.  Plants  have  preferences  as 
to  the  stocks  on  which  they  will 
grow;  but  we  can  find  out  what 
their  choice  is  only  by  making  the 
experiment.  The  pear  grows  well 
on  the  quince,  but  the  quince  does 
not  grow  so  well  on  the  pear.  The 
pear   grows  on   some  of  the  haw- 


41.  Triangular  leaf-cutting 
of  begonia  or  "beefsteak  geran- 
ium," with  the  leaf  of  a  young 
plant  starting   from  the   apex. 


28 


ARTIFICIAL   PROPAGATION 


thorns,  but  it  is  an  unwilling  subject  on  the  apple.  Tomato 
plants  will  grow  on  potato  plants,  and  potato  plants  on 
tomato  plants.  When  the  potato  is  the  root,  both  tomatoes 
and  potatoes  may  be  produced;  when  the  tomato  is  the 
root,  neither  potatoes  nor  tomatoes  will  be  produced.  Chest- 
nut will  grow  on  some  kinds  of  oak. 

72.  The  forming,  growing  tissue  of  the  stem  (on  the  plants 
we  have  been  discussing)  is  the  cambium,  lying  on  the  out- 
side of  the  woody  cylinder,  beneath  the  bark.  In  order  that 
union  may  take  place,  the  cambium  of  the  cion  and  of  the 


42.  Cion  of 


43.   The  cion  inserted. 


44.  The  parts  waxed. 


stock  must  come  together.  Therefore  the  cion  is  set  in  the 
side  of  the  stock.  There  are  many  ways  of  shaping  the  cion 
and  of  preparing  the  stock  to  receive  it.  These  ways  are 
dictated  largely  by  the  relative  sizes  of  cion  and  stock, 
although  many  of  them  are  matters  of  mere  personal  prefer- 
ence. The  underlying  principles  are  two:  securing  close 
contact  between  the  cambiums  of  cion  and  stock;  covering 
the  wounded  surfaces  to  prevent  evaporation  and  to  pro- 
tect the  parts  from  disease. 

73.  On  large  stocks,  the  commonest  form  of  grafting  is 


GRAFTING  29 

the  cleft-graft.  The  stock  is  cut  off  and  split;  and  in  one  or 
both  sides  a  wedge-shaped  cion  is  firmly  inserted.  Fig.  42 
shows  the  cion;  Fig.  43,  the  cions  set  in  the  stock;  Fig.  44, 
the  stock  waxed.  It  will  be  seen  that  the  lower  bud — that 
lying  in  the  wedge — is  covered  by  the  wax;  but  being  nearest 
the  food  supply  and  least  exposed  to  weather,  it  is  the  most 
likely  to  grow:  it  will  push  through  the  wax. 

74.  Cleft-grafting  is  performed  in  spring,  as  growth 
begins.  The  cions  are  cut  previously,  when  perfectly  dor- 
mant, and  from  the  the  tree  which  it  is  desired  to  propagate. 
The  cions  are  kept  in  sand  or  moss  in  the  cellar.  Limbs  of 
various  sizes  may  be  cleft-grafted, — from  one-half  inch  up 
to  four  inches  in  diameter;  but  a  diameter  of  one  inch  is  the 
most  convenient  size.  All  the  leading  or  main  branches  of 
a  tree-top  may  be  grafted.  If  the  remaining  parts  of  the 
top  are  gradually  cut  away  and  the  cions  grow  well,  the 
entire  top  will  be  changed  over  to  the  new  variety. 

Review. — How  do  we  determine  how  a  plant,  may  be  propagated? 
Mention  any  plants  that  grow  from  cuttings.  What  are  softwood 
cuttings?  Hardwood?  Describe  a  geranium  cutting.  What  is  the  proper 
condition  of  wood  for  making  a  softwood  cutting?  How  is  it  planted? 
Where?  In  what  kind  of  soil?  Give  directions  for  watering.  How  may 
cutting-wood  be  secured?  Describe  a  hardwood  cutting.  When  is  it 
made?  Name  plants  that  can  be  propagated  easily  by  means  of  hard- 
wood cuttings.  Describe  a  leaf-cutting.  What  is  a  cion?  Stock?  How 
do  we  find  out  what  stocks  are  congenial  to  the  cion?  Describe  a  cleft- 
graft.    When  is  cleft-grafting  performed?   Why  do  we  graft  ? 

Note. — The  cutting-box  may  be  set  in  the  window.  If  the  box 
does  not  receive  direct  sunlight,  it  may  be  covered  with  a  pane  of 
glass  to  prevent  evaporation.  Take  care  that  the  air  is  not  kept  too 
close,  else  the  damping-off  fungi  may  attack  the  cuttings,  and  they 
will  rot  at  the  surface  of  the  ground.  See  that  the  pane  is  raised  a 
little  at  one  end  to  afford  ventilation;  and  if  water  collects  in  drops  on 
the  under  side  of  the  glass,  remove  the  pane  for  a  time. 

Grafting-wax  is  made  of  beeswax,  resin,  and  tallow.  The  hands 
are  greased,  and  the  wax  is  then  worked  until  it  is  soft  enough  to  spread. 
For  the  little  grafting  which  any  pupil  would  do,  it  is  better  to  buy  the 
wax  of  a  seedsman.    However,  grafting  is  hardly  to  be  recommended 


30  ARTIFICIAL    PROPAGATION 

as  a  general  school  diversion,  as  the  making  of  cuttings  is;  and  this 
account  of  it  is  inserted  chiefly  to  satisfy  the  general  curiosity  on  the 
subject.  But  now  and  then  a  pupil  may  make  the  effort  for  himself, 
for  nothing  is  more  exciting  than  to  make  a  graft  grow  all  by  one's  self. 

The  pictures  of  the  cuttings  (Figs.  33-35,  37,  40)  and  the  grafts 
(Figs.  42-44)  are  one-third  natural  size. 

The  many  forms  of  grafting  and  budding  are  too  special  for  dis- 
cussion in  this  book.  Descriptions  of  them  may  be  found  in  "The 
Nursery-Book"  and  other  works. 


CHAPTER  VI 


FOOD    RESERVOIRS 


75.  Storehouses. — All  greatly  thickened  or  congested 
parts  are  reservoirs  for  the  storage  of  plant-food.  This 
food  is  mostly  starch  or  sugar.  Potatoes,  beets,  turnips, 
thick  rhizomes,  seeds,  are  examples.  Recall  how  potatoes 
sprout  in  the  cellar  (Fig.  45) :  the  sprouts  are  produced  from 
the  stored  food. 

76.  The  presence  of  starch  can  be  determined  by  apply- 
ing diluted  tincture  of  iodin  to  the  part:  if  a  blue  or  purplish 
brown  color  appears,  starch  is  present.  Cut  the  part  open  and 
moisten  the  fresh  sur- 
face with  iodin  (to  be 
had  at  the  drug  store) . 
The  test  will  usually 
give  the  best  reaction 
when  the  part  is  per- 
fectly dormant.  Starch 
may  be  found  in 
nearly  all  twigs  in  fall 
and  winter.  Test  thin 
cross-sections. 

77.  This  stored 
plant-food  enables  the 
plant  to  start  quickly 
in  the  spring,  without 
waiting  for  food  elab- 
oration to  begin  in  the 
leaves;  and  it  enables 
the    plantlet    in    the 


Potato  sprouts.  The  sprouts  have  Used  the  food 
Btored  in  the  tuber,  and  the  tuber  has  shriveled. 


(31) 


32 


FOOD    RESERVOIRS 


seed  to  grow  until  it  establishes  itself  in  the  earth.  The  flow- 
ers of  early-blooming  trees  are  developed  mostly  from  the 
nourishment  stored  in  the  twigs,  not  from  the  materials 


taken  in  at  the  time  by  the  roots,  nor  from  food  being  made 
by  the  newly  forming  leaves.  This  can  be  demonstrated 
by  bringing  branches  of  peach,  apple,  and  other  early- 
blooming  plants  into  the  house  in  the  winter  and  keeping 
them  in  water;  they  will  bloom  and  sometimes  even  make 
leaves.   Study  Fig.  46. 

78.  Kinds  of  Storage-organs. — Short  and 
much  thickened  or  swollen  parts  of  roots  or 
stems  are  known  as  tubers.  These  may  be 
stem-tubers,  as  the  potato,  or  root-tubers,  as 
the  sweet  potato  (45).  Most  tubers  are  sub- 
terranean. 

79.  Many  tubers  are  stem  at  the  top  and 
root  in  the  remaining  part:  these  are  called 
crown-tubers,  because  the  upper  part  comes 
to  the  surface  of  the  ground,  or  is  a  crown. 
Leaves  and  stems  arise  from  the  upper  part. 


TUBERS     AND     BULBS 


33 


Beet,  radish  parsnip,  turnip,  salsify,  carrot,  dahlia  roots, 
are  examples.  These  tubers  are  usually  much  longer  than 
broad,  and  generally  taper  down- 
wards. (Fig.  47.)  A  good  example  of 
stem-tuber  is  the  kohlrabi.  (Fig.  48). 


-tuber  above  ground. 
Kohlrabi. 


49.  A  multiplier  oni< 


80.  A  much  thickened  part  composed  of  scales  or  plates 
is  a  bulb.  The  bulb  may  be  scaly,  as  in  the  lily;  or  it  may  be 
tunicated, — made  up  of  plates  or  layers  within  layers,  as 
the  onion. 

81.  Small  bulbs  borne  amongst  the  foliage  or  flowers 
are  known  as  bulblets. 
Such  are  the  "top  onions," 
and  the  little  bulbs  that 
the  tiger  lily  (Fig.  31) 
bears  on  its  stem.  Bulbs 
that  grow  around  the  main 
bulb  or  which  are  formed 
by  the  breaking  apart  of 
the  main  bulb,  are  known 
as  bulbels.  Many  bulbous 
plants  propagate  by  means   50.  section  of 

G 


ultiplier  onion.   Natural  size. 


34 


FOOD   RESERVOIRS 


of  bulbels.  The  multiplier  or  potato  onion  (Fig.  49)  is  an 
example.  If  the  bulb  is  cut  across,  it  is  found  to  have  two 
or  more  "hearts"   or  cores  (Fig.  50).     When  it  has   been 

planted  a  week,  each  core 
or  part  begins  to  separate 
(Fig.  51),  and  there  are 
soon  as  many  onions  as 
there  are  cores.  Potato 
onions  can  be  bought  of 
seedsmen.  They  are  used 
for  the  raising  of  early 
onions. 

82.  Solid  bulb-like  parts 
are  known  as  conns.  These 
usually  have  a  loose  cover- 
ing, but  the  interior  is  not 
made  up  of  scales  or  plates. 
Of  such  are  gladiolus  and 
crocus  corms.  (Figs.  52,  53.)  Conns  multiply  by  cormels  or 
small  corms,  as  bulbs  do  by  bulbels;  or  the  plant  may  bear 
cormlets  amongst  the  branches  and  foliage.  Fig.  54  shows 
an  old  gladiolus  corm  on  which  three  new  corms  have  grown. 
83.  We  have  seen  that  thickened  parts  may  serve  one 
or  both  of  two  purposes:  they  may  be  storage-organs  for 


51.   beginning  to 

Each  part  will  be  a 


52.  Corm  of  crocus.    Nat.  size. 


53.  Section  of  a  crocus  corm. 


TUBERS     AND     BULBS 


35 


food;  they  may  be  means  of  propagating  the  plant.  The 
storage  of  food  carries  the  plant  over  a  dry  or  cold  season. 
By  making  bulbs  or  tubers,  the  plant  persists  until  spring. 
Future   growth   is,    therefore,    pro-  ~ 

vided  for  by  the  storage.   Bulbous  /%$        ] 

plants   are   characteristic   of  many 
dry  countries. 


54.  Three  corms  growing  on  an 
old  one. — Gladiolus. 


Review. — What  do  you  understand 
by  food  reservoirs?  How  is  the  presence 
of  starch  determined?  Where  may  starch 
be  found?  Of  what  service  to  the  plant  is 
this  stored  food?  How  are  the  flowers  and 
[eaves  enabled  to  start  so  early  in  spring? 
Define  tuber.  Root-tuber.  Stem-tuber.  Crown-tuber.  Give  examples. 
Define  bulb.  Scaly  bulb.  Tunicated  bulb.  Bulblet.  Bulbel.  Give 
examples.  Define  corm.  Cormel.  What  two  purposes  do  congested 
parts   serve? 

Note. — The  pupil  should  examine  various  kinds  of  bulbs  and 
tubers.  If  these  are  not  at  hand,  many  kinds  can  be  purchased  of 
seedsmen  or  florists.  Secure  onion,  narcissus,  hyacinth,  gladiolus, 
crocus,  potato.  Cut  them  in  two.  Study  the  make-up.  Test  them 
for  starch.  Plant  some  of  them  in  pots  or  boxes.  Observe  how  they 
grow.  In  the  onion  and  some  other  plants,  most  of  the  stored  food  is 
sugar.  Place  a  potato  tuber  in  a  tumbler  or  cup  in  a  window  so  that 
the  bottom  of  the  tuber  will  be  in  the  water. 


CHAPTER  VII 

WINTER  BUDS 

84.  What  Buds  Are. — Because  of  cold  or  dry  weather, 
the  plant  is  forced  into  a  period  of  inactivity.  We  have 
seen  that  it  stores  food,  and  is  ready  to  make  a  quick  start 
in  the  spring.  It  also  makes  embryo  branches  and  packs 
them  away  underneath  close-fitting  scales:  these  branch- 
lets  and  their  coverings  are  winter  buds.  The  growing 
points  of  the  plant  are  at  rest  for  a  time.  In  the  warm 
season,  the  growing  point  is  active,  and  the  covering  of 
scales  is  not  so  pronounced.  A  winter  bud  may  be  defined 
as  a  resting  covered  growing  point. 

85.  A  resting  bud,  therefore,  is  a  shortened  axis  or  branch, 
bearing  miniature  leaves  or  flowers,  or  both,  and  protected 
by  a  covering.  Cut  in  two,  lengthwise,  a  bud  of  the  horse- 
chestnut  or  other  plant  that  has  large  buds.  With  a  pin, 
separate  the  tiny  leaves.    Count  them.    Examine  the  big 

bud  of  the  rhubarb  as  it  lies  under 
the  ground  in  winter  or  early  spring. 
Dissect  large  buds  of  the  apple  and 
and  pear.    (Figs.  55,  56.) 

86.  The  bud  is  protected  by  firm 
.    '"      and  dry  scales;  but  these  scales  are 
Bud  of  apn-   only    modified    leaves.     The    scales 

cot  showing  ,    .  56.  Bud  of  pear 

the   minia-   fit  close.    Often  the  bud  is  protected      showing  both 

ture  leaves.    by  varnish   (see  horse-chestnut  and      ^   aTnhe 

the   balsam   poplars).     Most   winter   buds   are      latter  are  the 

^    L  '  .  little  knobs  in 

more    or    less    woolly.     Examine    them    under      the  center. 
a  lens.    As  we  might  expect,  bud-coverings  are  most  prom- 
inent in  cold  and  dry  climates. 
(36) 


MANY    KINDS    OF    BUDS 


37 


> 


c 


87.  Where  Buds  Are. — Buds  are  borne  in  the  axils 
of  the  leaves, — in  the  acute  angle  that  the  leaf  makes  with 
1^  the  stem.  When  the  leaf  is  grow- 
ing in  the  summer,  a  bud  is  form- 
ing above  it.  When  the  leaf  falls, 
the  bud  remains,  and  a  scar  marks 
the  place  of  the  leaf.  Fig.  57 
shows  the  large  leaf-scars  of  ailan- 
thus.  Observe  those  on  the  horse- 
chestnut,  maple,  apple,  pear,  bass- 
wood,  hickory,  or  any  tree  or  bush. 
88.  Sometimes  two  or  more  buds 
are  borne  in  one  axil:  the  extra 
ones  are  accessory  or  supernumerary  s8.  Termi- 
buds.  Observe  them  in  the  Tar-  between 
tarian  honeysuckle  (common  in  bWu°d°th— 
yards),  walnut,  butternut,  red  Cum"lt' 
maple,  honey  locust,  and  sometimes  in  the  apricot  and 
peach. 

89.  Shoots  of  many  plants  bear  a  bud  at  the  tip:  this 
is  a  terminal  bud.  It  continues  the  growth  of  the  axis  in 
a  direct  line.    Very  often  three  or  more  buds  are  clustered 


Leaf-scars.- 

Ailanthus. 


«:-%f*  "-.•- x 


at  the  tip  (Fig.  58); 
and  in  this  case  there 
may  be  more  buds  than 
leaf-scars.  Only  one  of 
them,  however,  isstrictly 
terminal. 

90.  Bulbs  and  cabbage 
heads  may  be  likened 
to  buds:  that  is,  they 
are  condensed  stems, 
with  scales  or  modified 
leaves  densely  overlapping  and  forming  a  rounded  body. 
(Fig.  59.)    They  differ  from  true  buds,  however,  in  the  fact 


59.  A  gigantic  bud. — CalibMgc 


38 


WINTER    BUDS 


that  they  are  condensations  of  main  stems  rather  than 
embryo  stems  borne  in  the  axils  of  leaves.  But  bulblets 
may  be  scarcely  distinguish- 
able from  buds  on  the  one 
hand  and  from  bulbs  on  the 
other.  Cut  a  cabbage  head  in 
two  lengthwise,  and  see  what 
it  is  like. 

91.  What  Buds  do.— A  bud 
is  a  growing  point.  In  the 
growing  season  it  is  small, 
and  persons  do  not  notice  it. 
In  the  winter  it  is  dormant 
and  wrapped  up  and  is  plainly 
seen:  it  is  waiting.  All  branches  spring  from 
buds. 

92.  All  winter  buds  give  rise  to  branches, 
not  to  leaves  alone:  that  is,  the  leaves  are  borne 
on  the  lengthening  axis.  Sometimes  the  axis, 
or  branch,  remains  very  short, — so  short  that  it 
may  not  be  noticed.  Some- 
times it  grows  several  feet 
long. 

93.  Whether  the 
branch  grows  long 
or  not  depends  on 
the    chance    it    has, 

— position  on  the  plant,  fertility 

of    soil,     rainfall,     and    many 

other  things.    The  new  shoot  is 

the  unfolding  and  enlarging  of 

the  tiny  axis  and  leaves  that 

we  saw  in  the  bud.     (Figs.  55, 

56.)   If  the  conditions  are  congenial,  the  shoot  may  form  more 

leaves  than  were  tucked  away  in  the  bud,  but  commonly 


^0.  Willow. 
The  "pus- 
sies" are 
pushing 
out,  and 
a  large 
black  bud 
scale  is 
ready  to 
fall  from 
the  base 
of  each. 


64.    Growth  is 
progressing. 


CONTENTS     OF     BUDS 


39 


65.  Opening  of  the 
pear  bud. 


it  does  not.    The  length  of  the  shoot  usually  depends  more 

on  the  lengths  between  joints  than  on  the  number  of  leaves. 
94.  How   Buds    Open. — When   the   bud 

swells,    the   scales    are   pushed   apart,    the 

little   axis   elongates   and   pushes  out.     In 

most  plants,  the  outside  scales  fall  very  soon, 

leaving  a  little  ring  of  scars.    Notice  peach, 

apple,    plum,    willow,    and    other    plants. 

(Fig.  GO.)     In   others,  all    the  scales  grow 

for  a  time,  as  in  the  pear.  (Figs.  61,  62.) 
In  other  plants,  the  inner  bud- 
scales  become  green  and  al- 
most leaf-like.  See  the  maple 
and  hickory.  Fig.  63  shows  a 
hickory  bud.  Two  weeks  later, 
the  young  shoot  had  pushed  out 
and  the  enlarged  scales  were  hanging.  (Fig.  64.) 
95.  Sometimes  flowers  come  out  of  the  buds. 
Leaves  may  or  may  not  accompany  the  flowers. 
We  saw  the  embryo  flowers  in  Fig.  56.  The 
bud  is  shown  again  in  Fig.  61.  In  Fig.  62  it  is 
opening.     In  Fig.  65  it  is 

more  advanced,   and  the  woolly  un- 
formed   flowers    are    appearing.      In 

Fig.  66  the  growth  is  more  advanced. 

In  Fig.  67  the  flowers  are  full  blown; 

and  the  bees  have  found  them. 

96.  Buds  that  contain  or  produce 

only  leaves  are  leaf-buds.    Those  that 

contain   only   flowers   are  flower-buds 

or  fruit-buds.     The    latter   occur   on 

peach,    almond,    apricot,    and    many 

very     early    spring-flowering    plants.        67-  p,:u  '" '""  bloom- 

(Fig.  68.)     The  single  flower  is  emerging  from  the  apricot 

bud  in  Fig.  69.    Those  that  contain  both  leaves  and  flow- 


40 


WINTER    BUDS 


Almond  flower — the 
sole  occupant  of  a  bud. 


ers  are  mixed  buds,  as  in  pear  (Fig.  67),  apple,  and  most  late 

spring-flowering  plants. 

97.  Fruit-buds  are  usually  thicker 
or  stouter  than  leaf-buds.  They  are 
borne  in  different  positions  on  differ- 
ent plants.  In  some  plants 
(apple,  pear)  they  are  mostly 
on  the  ends  of  short  branches 
or  spurs;  in  others  (peach,  red 
maple)  they  are  mostly  along 
the  sides  of  the  last  year's 
growths.  In  Fig.  70  are  shown 
three  fruit-buds  and  one  leaf- 
bud     on     e,     and     leaf-buds 

on  a.    In  Fig.  71  a  fruit-bud  is  at  the  left,  and  a  leaf-bud 

at  the  right. 

98.  The      "Burst      of     Spring" 

means  chiefly  the  opening  of  the 

buds.    Note  the  process  in  Fig.  72. 

Everything  was  made  ready  in  the 

previous  growing  season.  The  em- 
bryo shoots  and  flowers  were  devel- 
oped in  the  buds,  and  the  food  was 

stored.  Spring  comes  on.  The  warm 

rain  falls,  and  the  shutters  open  and 

the  sleepers  wake:   the   frogs  peep 

and  the  birds  come. 


Review. — What  are  resting  buds? 
What  are  they  for?  What  is  their  cover- 
ing? Where  are  they  borne?  When  are 
they  formed?  What  is  a  leaf-scar?  What 
are  accessory  buds?  What  other  name  is 
applied  to  them?  Define  terminal  bud. 
What  does  it  do?  What  are  bulbs  and 
cabbages?  How  do  they  differ  from 
buds?    What  do  buds  do?    From  what  do 


Fruit-buds  and  leaf-buds 
of  pear. 


QUESTIONS     ON     BUDS 


41 


branches  arise?  To  what  do  winter  buds  give  rise?  What  determines 
whether  the  branch  shall  be  long  or  short?  Describe  the  opening  of 
a  bud.  What  are  flower-buds?  Leaf -buds? 
Mixed  buds?  How  may  fruit-buds  be  distin- 
guished?   What  is  the  "burst  of  spring?" 

Note. — It  is  easy  to  see  the  swelling  of  the 
buds  in  a  room  in  winter.  Secure  branches  of 
trees  and  shrubs,  two  to  three  feet  long,  and 
stand  them  in  vases  or  jars,  as  you  would 
flowers.  Renew  the  water  frequently  and  cut 
off  the  lower  ends  of  the  shoots  occasionally' 
In  a  week  or  two  the.  buds  will  begin  to  swell. 
Of  red  maple,  peach,  apricot,  and  other  very 
early-flowering  things,  flowers  may  be  secured 
in  ten  to  twenty  days.    Try  it. 

The  shape,  size,  and  color  of  the  winter  buds 
are  different  in  every  kind  of  plant.  By  the  buds 
alone  botanists  are  often  able  to  distinguish  the 
kinds  of  trees.  Even  such  similar  plants  as  the  different  kinds  of 
willows  have  good  bud  characters.  The  study  of  the  kinds  of  buds 
affords  excellent  training  of  the  powers  of  observation. 


Fruit-bud  and  leaf- 
bud  of  apple. 


72.  The  burst  of  spring  in  the  lilac. 


CHAPTER   VIII 


PLANTS   AND    SUNLIGHT 


99.  Each  Plant  Responds  to  Light. — Green  plants  live 
only  in  sunlight,  direct  or  indirect.  The  gradual  with- 
drawal of  light  tends  to  weaken  the  plant;  but  the  plant 

makes  an  effort  to  reach  the  light 
and  therefore  grows  toward  it.  The 
whole  habit  of  a  plant  may  be 
changed  by  its  position  with  ref- 
erence to  sunlight.  Choose  two 
similar  plants.  Place  one  near 
the  window  and  the  other  far 
from  it.  Watch  the  behavior  from 
day  to  day.  Fig.  73  shows  a 
fern  that  grew  near  the  glass  in 
a  conservatory:  Fig.  74  shows  one  that  grew  on  the 
floor  of  a  conservatory.  Fig.  74  also  teaches  another 
lesson,  which  is  to  be  explained  in  another  chapter  (Chapter 
XXVIII). 

100.  Plants  grow  toward  the  light.  The  most  vigor- 
ous branches,  as  a  rule,  are  those  that  receive  most  light. 


73.  Sufficient  light. 


75.  Growing  toward  the  light. 


REACHING    FOR    LIGHT 


43 


Climb  a  tree  and   observe  where  the  thriftiest  shoots  arc; 
or  observe  any   bush. 

101.  When  plants  or  their  parts  are  not  stiff  or  rigid, 


76.  Branches  of  the  cedar  reaching  for  light. 

they  turn  toward  the  light,  if  the  light  comes  mostly  from 
one  direction.  The  geraniums  and  fuchsias  in  the  window 
arc  turned  around  occasionally  so  that  they  will  grow  sym- 
metrical. Plant  radish  in  a  pot  or  pan.  When  the  plants 
are  three  or  four  inches  high,  place  the  pan  in  a  tight  box 


44 


PLANTS   AND    SUNLIGHT 


which  has  a  hole  on  one  side.  The  next  day  it  will  look 
like  those  in  Fig.  75.  This  turning  toward  the  light  is 
called  heliotropism  (helios  is  Greek  for  "sun"). 

102.  Even  under  natural 
conditions,  plants  become 
misshapen  or  unsymmetri- 
cal  if  the  light  comes 
mostly  from  one  direction. 
On  the  edge  of  a  forest, 
the  branches  grow  #out 
toward  the  light.  (Fig.  76.) 
Trees  tend  to  grow  away 
from  a  building.  Branches 
become  fixed  in  their 
position,  so  that  even  in 
winter  they  show  the  in- 
fluence of  light. 

103.  Some  plants  climb 
other  plants  in  order  to 
reach  the  sunlight;  or  they 
climb  rocks  and  buildings.  Notice  that  the  vine  on  the  house 
luxuriates  where  it  is  lightest.  Climbing  plants  may  injure 
or  even  kill  the  plant  on  which  they  climb.  This  they  may 
do  by  throwing  their  mantle  of  foliage  over  it,  and  smother- 
ing it,  or  by  sending  their  roots  into  its  trunk  and  robbing 
it  of  food.   Sometimes  they  do  both,  as  in  Fig.  78. 

104.  Each  Branch  Grows  Toward  Light. — The  plant  is 
made  up  of  branches.  There  is  a  struggle  amongst  the 
branches  for  sunlight.  We  have  seen  (Fig.  7)  that  no  two 
branches  are  alike:  we  now  know  one  reason  why.  Notice 
that  the  small  branches  die  in  the  center  of  the  tree.  Look 
on  the  inside  of  a  pine,  spruce  or  other  dense  tree.  Every 
branch  has  a  story  to  tell  of  the  value  of  sunlight. 

105.  Each  Leaf  Grows  Toward  Light. — Leaves  are  borne 
toward    the   ends   of   the   branches.     This   is   particularly 


77.  Mantle  of  clematis.    The  leaves,  and  later 
the  flowers,  spread  themselves  to  the  light. 


THE    LIGHT    REACTION 


45 


marked  when  the  struggle  is  severe.  If  the  outside  of  a 
plant  is  densely  thatched  with  leaves,  the  inside  will  be 
found  to  be  comparatively  bare.  Contrast  Figs.  79  and  80, 
both  being  views  of  one  tree.  We  know  the  tree  as  seen 
in  Fig.  79:   the  squirrel  knows  it  as  seen  in  Fig.  80. 

106.  On  any  branch  in  a  very  thick-topped  tree  or  bush, 
leaves  of  equal  age  usually  tend  to  be  largest  where  the 
light  is  best.  Leaves  that  grow  in  full  sunlight  tend  to  per- 
sist later  in  the  fall  than  those  that  grow  in  poor  light. 
This  fact  is  sometimes  obscured  because  the  outermost 
leaves  are  most  ex- 
posed to  autumn 
winds. 

107.  Plants  that 
start  in  cellars,  from 
seeds,  bulbs,  or  tubers, 
grow  until  the  stored 
food  is  exhausted  and 
then  die:  the  leaves 
do  not  develop  to  full 
size  in  darkness.  Figs. 
81  and  82  show  this. 
Fig.  81  is  rhubarb 
forced  in  a  cellar  for 
the  winter  market; 
Fig.  82  is  a  plant 
grown  out-of-doors. 
Compare  Fig.  45. 

108.  The  position 
or  direction  of  leaves 
is  determined  largely 
by  exposure  to  sun- 
light. In  temperate  climates,  they  usually  hang  in  such  a 
way  that  they  receive  the  greatest  amount  of  light.  Observe 
the  arrangement  of  leaves  in  Fig.  83.    One  leaf  shades  the 


8.   A  olimbing  Iir  choking  a  palm. 


46 


PLANTS   AND    SUNLIGHT 


79.  Looking  at  the  top  of  a  Norway  maple. — As  the  bird  sees  it. 

other  to  the  least  possible  degree.  If  the  plant  were  placed 
in  a  new  position  with  reference  to  light,  the  leaves  would 
make  an  effort  to  turn  their  blades.  Observe  the  shingle-like 
arrangement  in  Fig.  79.    If  the  pupil  were  to  examine  the 


3.  Looking  up  into  the  same  tree. — As  the  squirrel 


THE    LICHT    RELATION 


47 


leaves  on  the  Norway  maple,  which  is  photographed  in  Fig. 
79,  he  would  find  that  leaves  which  are  not  on  the  outside 
lengthen  their  leaf-stalks  in  order  to  get  the  light.  See  Fig. 
157.    Norway  maple  is  common  on  lawns  and  roadsides. 

109.  We  have  seen  (85)  that  a  large  part  of  the  leaves 
of  any  one  year  are  packed  away  in  the  buds  of  the  previous 
winter.  It  is  almost  impossible  that  these  leaves  should  be 
packed  away  hit  or  miss.  They  are  usually  arranged  in  a 
mathematical  order.  We  can  see  this  order  when  the  shoot 
has  grown.    We  can  see  it  by  studying  the  buds  on  recent 


shoots,  since  there  was  a  leaf  for  each  bud.  The  leaves  (or 
buds)  may  be  opposite  each  other  on  the  stem,  or  alternate. 
(Fig.  84.) 

110.  When  leaves  are  opposite,  the  pairs  usually  alter- 
nate. That  is,  if  one  pair  stands  north  and  south,  the  next 
pair  stands  east  and  west.  See  the  box-elder  shoot,  on 
the  left  in  Fig.  84.  One  pair  does  not  shade  the  pair  beneath. 
The  leaves  are  in  four  vertical  ranks. 

111.  There  are  several  kinds  of  alternate  arrangement. 
In  the  elm  shoot  in  Fig.  84,  the  third  bud  is  vertically  above 
the  first.    This  is  true,  no  matter  which  bud  is  taken  as  the 


48 


PLANTS    AND    SUNLIGHT 


starting  point.  Draw  a  thread  around  the  stem  until  the 
two  buds  are  joined.  Set  a  pin  at  each  bud.  Observe  that  the 
two  buds  are  passed  (not  counting  the  last)  and  that  the 
thread  makes  one  circuit  of  the  stem.  Representing  the  num- 
ber of  buds  by  a  denominator,  and  the  number  of  circuits 
by  a  numerator,  we  have  the  fraction  ]/2,  which  expresses 
the  part  of   the   circle   that   lies   between   any  two  buds. 

That  is,  the  buds  are 
one-half  of  360  de- 
grees apart,  or  180 
degrees.  Looking 
endwise  at  the  stem, 
the  leaves  are  seen 
to  be  2-ranked.  Note 
that  in  the  apple 
shoot  (Fig. 84, right), 
the  thread  makes 
two  circuits  and  five 
buds  are  passed: 
two-fifths  represents 
the  divergence  be- 
tween the  buds.  The 
leaves  are  5-ranked. 
112.  Every  plant 
has  its  own  arrange- 
ment of  leaves.  For 
opposite  leaves,  see 
maple,  box-elder,  ash,  lilac,  honeysuckle,  mint,  fuchsia.  For 
2-ranked  arrangement  see  all  grasses,  Indian  corn,  basswood, 
elm.  For  3-ranked  arrangement  see  all  sedges.  For  5-ranked 
(which  is  one  of  the  commonest),  see  apple,  cherry,  pear, 
peach,  plum,  poplar,  willow.  For  8-ranked,  see  holly,  osage 
orange.  More  complicated  arrangements  occur  in  bulbs, 
house-leeks,  and  other  condensed  parts.  The  arrangement 
of   leaves   on   the   stem   is   known   as   phyllotaxy   (literally 


82.   Rhubarb  growing  in  the  light. 


LEAF   ARRANGEMENT 


49 


S3.  All  the  leaves  are  exposed 
to  light. 


"leaf-arrangement").  Make  out  the 
phyllotaxy  on  any  plant.  Try  it 
on  a  long  potato  tuber. 

113.  In  some  plants,  several 
leaves  occur  at  one  level,  being 
arranged  in  a  circle  around  the 
stem.  Such  leaves  are  said  to  be 
verticillate  or  whorled.  Leaves 
arranged  in  this  way  are  usually 
narrow. 

114.  Although  a  definite 
arrangement  of  leaves  is  the  rule 
in  most  plants,  it  is  subject  to  mod- 
ification. On  shoots  that  receive  the  light  only  from  one 
side  or  that  grow  in  difficult  positions,  the  arrangement  may 
not  be  definite.  Examine  shoots  that  grow  on  the  under 
side  of  dense  tree-tops  or  in  other  partially  lighted  positions. 

115.  The  direction  or 
"hang"  of  the  leaf  is 
usually  fixed,  but  there 
are  some  leaves  that 
change  their  direction  be- 
tween daylight  and  dark- 
ness. Thus,  leaves  of 
clover  (Fig.  85),  bean, 
locust,  and  many  related 
plants,  "sleep"  at  night; 
also  oxalis.  It  is  not  a 
sleep  in  the  sense  in  which 
animals  sleep,  however, 
but  its  function  is  not 
well  understood. 

116.  Leaves  usually  ex- 
pose one  particular  surface 
to  the  light.     This  is  be- 


50 


PLANTS    AND    SUNLIGHT 


85.   Day  and  night  positions  of  the 
clover  leaf. 


cause  their  internal  structure  is  such  that   light  is   most 

efficient  when  it  strikes  this  surface,  as  we  shall  learn  later 

on.  Some  plants,  how- 
ever, expose  both   surfaces 

to  the  light,  and  their  leaves 

stand    vertical.      Others 

avoid    the  intense   light   of 

midday    and    turn    in    the 

direction    of     least     light. 

Leaves    standing    edgewise 

are  said  to  exhibit  -polarity. 

They  are  "compass  plants"  if  they  point  north  and  south. 
The  famous  compass  plant  or  silphium  of 
the  prairies,  and  the  wild  lettuce  (Fig.  86), 
are  examples  of  plants  having  polar  leaves. 
Every  leaf  has  a  story  to  tell  of  the  value  of 
sunlight. 

117.  Winter  Buds  Show  What  Has  Been 
the  Effect  of  Sunlight. — Buds  are  borne  in 
the  axils  of  the  leaves  (87),  and  the  size  or 
vigor  of  the  leaf  determines  to  a  large  extent 
the  size  of  the  bud.  Notice  that,  in  most 
instances,  the  largest  buds  are  nearest  the  tip. 
(Fig.  87.)  If  the  largest  ones  are  not  near  the 
tip,  there  is  some  special  reason  for  it.  Ex- 
amine the  shoots  on  trees  and  bushes. 

118.  The  largest  buds  usually  start  first 
in  spring,  and  the  branches  that  arise  from 
them  have  the  advantage  in  the  struggle 
for  existence.  Plants  tend  to  grow  most  vig- 
orously from  their  ends.  Observe  that  only 
the  terminal  bud  grew  in  the   hickory  twig 

86ieuucde?arweedk^  in  Fig.  64.  If  the  side  buds  or  lower  buds 
wMteldpiaace^  grew  more  vigorously  than  the  end  buds,  the 
l^ss Tert^aL6  °r  plant   would    become   exceedingly   branched 


QUESTIONS   ON   THE    LTGHT-RELATION  51 

and  its  whole  form  might  be  changed.  Consider  how  such  a 
mode  of  branching  would  affect  any  small  tree  that  you 
know.  Every  bud  has  a  story  to  tell  of  the  value  of  sunlight. 

Review.— What  is  the  relation  of  the  plant 
to  sunlight?  Does  its  form  ever  depend  on  its 
relation  to  light?  In  what  direction  do  the  tops 
of  plants  grow?  Where  are  the  most  vigorous 
branches?  What  is  heliotropism?  Why  are  trees 
sometimes  unsymmetrical?  Do  you  know  any 
instance's  yourself?  What  is  one  way  in  which 
plants  profit  by  the  climbing  habit?  Explain. 
Where  are  leaves  borne  in  reference  to  light? 
Where  are  leaves  usually  largest?  Do  they  de- 
velop in  darkness?  Are  leaves  borne  directly 
above  i  >ne  another?  How  may  leaves  be  arranged? 
Explain  what  phyllotaxy  is.  Are  leaves  always 
arranged  definitely?  Explain  the  arrangement 
in  sonic  plant  that  is  not  mentioned  in  this 
lesson.  What  is  the  "sleep"  of  leaves?  Which 
surface  of  the  leaf  is  exposed?  What  are  com- 
pass plants?  How  do  buds  show  what  the  effect 
of  sunlight  has  been?  What  buds  start  first  in  37.  The  bis  terminal 
spring?  buds. — Hickory- 


CHAPTER  IX 

STRUGGLE   FOR   EXISTENCE   AMONGST 
THE   BRANCHES 

119.  No  Two  Branches  are  Alike. — Every  twig  has  a 
history.  It  has  to  contend  for  sunlight  and  a  place  in  which 
to  grow.  Its  size  and  shape,  therefore,  depend  on  the  con- 
ditions under  which  it  lives.  Observe  the  long,  straight, 
big-leaved  shoots  on  the  top  of  the  plant,  and  the  short, 
weak,  crooked  ones  on  the  inside  or  under  side. 

120.  There  is  struggle  for  existence  for  every  twig  and 
every  leaf.   Those  finding  the  best  conditions  live  and  thrive ; 


88.  The  struggle  for  life. — Mulberry  shoot. 

those  finding  the  poorest  die.  The  weak  are  overpowered 
and  finally  perish:  this  prunes  the  tree,  and  tends  to  make 
the  strong  the  stronger.  Observe  the  competition  in  the 
branch  photographed  in  Fig.  88.  Pick  out  the  dead  twigs, 
the  weak  ones,  the  strong  ones.   See  also  Fig.  7. 

121.  The  Buds  May  Not  Grow. — There  is  not  room  in  a 
tree-top  for  all  the  buds  to  grow  into  branches.    Some  buds 
(52) 


THK    STRUGGLE    FOR    EXISTENCE 


53 


89.  The  branching  is  crooked 
and  irregular. 


are  suppressed.    Branches  die.    So  it  comes  that  branches 
are  not  arranged  regularly,  although  the  buds  may  be.    In 

the  Tartarian  or  "tree" 
honeysuckle  the  buds  are 
opposite ;  Fig.  89  shows  how 
the  branches  are.  Even 
though  the  branch  or  plant 
is  apparently  regular  in 
shape  (as  in  Fig.  90),  never- 
theless many  of  the  buds 
have  been  suppressed,  else 
there  would  be  a  branch 
from  every  axil. 

122.  The  results  of  the 
struggle  for  existence  in  the 
tree-top  can  be  expressed  in  figures.  Consider  that  every  bud 
is  the  germ  or  starting  point  of  a  branch.  Observe  at  what 
distances  apart  the  buds  are  usually  borne  on  any  plant,  and 
estimate  the  number  of  buds  that  the  plant  has  borne: 
count  the  number  of  branches  which  the  tree  actually  bears. 
It  will  be  found  that  the  number  of  buds  is  far  in  excess  of 
the      number      of 


branches:  the  differ- 
ence between  the 
numbers  shows  how 
many  buds  or 
branches  have  failed. 
Or,  count  the  buds 
on  any  branch,  and 
figure  up  the  pos- 
sibilities. A  branch 
12  inches  long,  for 
example,  has  10  buds. 
If  each  bud  grows, 
at  the  end  of  the  next 


Not  all  t 
branches 


ids  have  produc 
■Tea  plant. 


54 


STRUGGLE   AMONGST   BRANCHES 


season,  there  will  be  10  branches,  each  of  which  may  have 
10  buds.  At  the  end  of  the  second  year  there  will  be  100 
branches;  at  the  end  of  the  third,  1,000.  Can  1,000  branches 
be  borne  on  a  4-year-old  branch  12  inches  long,  as  a  base? 
Or,  count  the  old  bud-scars  on  the  branches — for  the  places 
of  the  buds  persist  as  wrinkles  in  the  bark,  often  for  many 
years.  (Fig.  91.)  One  can  often 
locate  these  bud-scars  on  old 
branches  with  his  eyes  closed  by 
running  his  fingers  over  the  bark. 
123.  Buds  that  fail  to  grow 
are  called  dormant  buds.  They 
are  usually  the  weakest  ones, — 
those  which  grew  in  the  most 
uncongenial  conditions.  They  are 
toward  the  base  of  the  shoot. 
We  have  seen  (118)  that 
it  is  the  terminal  or 
uppermost  buds  which 
are  most  likely  to  grow. 
The  dormant  buds 
gradually  die.  They 
may  live  four  or  five 
years  on  some  plants. 
If  the  other  buds  or 
branches  fail  or  are  in- 
jured, they  may  grow, 
but  usually  they  do  not. 
124.  Dormant  buds  must  not  be  confounded  with  ad- 
ventitious buds.  We  have  learned  (54)  that  adventitious 
buds  are  those  formed  at  unusual  times  or  places,  because 
of  some  disturbance  of  the  part.  If  a  large  branch  is  cut 
off,  suckers  or  watersprouts  are  thrown  out  near  the  wound: 
these  arise  from  buds  that  are  made  for  the  occasion.  These 
buds  did  not  exist  there.    In  many  countries  it  is  a  custom 


Scars  of  the  dormant  buds. — Willow. 


92.  A  pollard  tree 
In  this  case,  man  has  added  to  the  struggle  for  existence.    An  ash  tree  in  Alger 
The  shoots  are  cut  for  forage. 


(55) 


56 


STRUGGLE   AMONGST   BRANCHES 


to  "pollard"  or  cut  off  the  tops  of  trees  every  few  years  for 
the  firewood  or  other  uses,  and  strong  adventitious  shoots 

arise    along    the    trunk. 


(Fig:  92.) 

125.  Where  the 
Branches  Grow. — Be- 
cause new  shoots  tend 
to  arise  from  the  top 
of  the  twigs,  the  branches 
of  most  trees  are  in  tiers 
or  layers.  These  tiers  of- 
ten can  be  traced  in  trees 
50  and  100  years  old. 
Try  it  in  any  oak,  maple, 
ash,  or  other  tree.  For 
practice,  begin  with 
young,  vigorous  trees. 
(Figs.  93  and  94.) 

126.  When  part  of  a 
top  is  removed,  the  remaining  branches  fill  the  space.  The 
branches  are  attracted  by  the  light,  and  grow  in  that 
direction.  A  pruned  or  injured  top  always  tends  to  come 
back  to  equilibrium. 


93.  Tiers  of 
branches  on 
young  tree. 


94.  Even  in  old  trees 
the  tiers  can  be 
traced. 


95.  Crushed  by  storm,  the  tree  still  shoots  upward. 


HISTORY    OF    A    TWIG 


57 


127.  A  mangled  or  broken  plant  tends  to  regain  its  former 
position.  From  fallen  trees,  upright  shoots  arise.  In  Fig. 
95  observe  the  new  trunks  arising  from  the  older  prostrate 
trunks. 


^' •>       W  °7-  The  same  shoot-  APril  20- 


'<■'  VBi;     K 


m 


Review. — What  is  meant  by  the  statement  thai  every  twig  has 
a  history?  Upon  what  docs  the  shape  and  size  of  a  branch  depend? 
Explain  what  you  mean  by  the  struggle  for  existence.  Why  do  not  all 
buds  grow?  If  buds  arc  arranged  in  mathematical  order,  why  arc  not 
branches  so  arranged'.'  How  may  the  effect  of  struggle  for  existence  be 
expressed  in  figures?  Choose  some  branch  and  explain.  Define  dormant 
buds.  Adventitious  buds.  Why  arc  branches  in  tiers,  or  borne  at 
intervals?  How  do  plants  tend  to  regain  their  form  and  position,  when 
injured? 

Note. — Let  the  pupil  work  out  the  history  of  some  branch.  It  is 
better  to  choose  a  branch  that  is  vigorous.  He  should  first  determine, 
if  the  shoot  is  dormant,  how  much  grew  the  previous  season.  The 
last  year's  growth  bears  buds  on  the  main  axis,  not  on  side  branches; 


58 


STRUGGLE   AMONGST   BRANCHES 


and  the  "ring"  (scars  or  bud-scales)  marks  the  junction  between  the 
different  years'  growth.  Notice  this  ring  in  the  front  shoot  in  Fig.  87. 
The  teacher  will  find  many  twigs  worked  out  in  "Lessons  with  Plants." 
Figs.  96-100  show  an  actual  case.  These  drawings  were  all  made  with 
the  greatest  care  from  one  elm  twig.  The  twig  (Fig.  96)  shows  three 
years'  growths.  The  side  branch  is  evidently  only  one  year  old,  for  it 
did  not  arise  until  the  twig  which  bears  it  was  one  year  old.  Note 
that  only  one  of  the  buds  made  a  branch.  There  are  five  blossom-buds. 
Fig.  97  shows  the  twig  in  bloom.  Fig.  98  shows  it  in  fruit  and  leaf. 
Fig.  100  shows  the  net  result.  The  side  branch  grew  from  a  to  s  and  made 
two  blossom  buds.  The  tip  of  the  main  shoot  (Fig.  96)  was  broken  in 
a  storm.  The  two  buds  next  in  succession  grew.  Each  made  flower- 
buds.   Observe  how  many  buds  on  this  elm  shoot  have  failed. 


100.  October  18. 


CHAPTER   X 

PRUNING 

128.  We  are  now  ready  to  discuss  the  reasons  for  pruning, 
and  how  the  work  should  be  performed.  We  have  discovered 
that  there  is  competition  between  different  plants  and  also 

between  branches  on  the  same  plant. 
When  one  or  more  of  the  competitors 
is  removed,  the  remain- 
ing plants  or  parts 
have  better  condi- 
tions and  will  prob- 
ably increase  in  vigor. 
Pruning  is  a  means  of 
allowing  the  remaining 
branches  a  better  op- 
portunity to  develop. 

129.  Pruning  should  therefore  increase 
the  vigor  of  remaining  parts.  In  fruit  trees 
it  also  thins  the  fruit,  increasing  its  size. 
It  opens  a  tree-top  to  air  and  light; 
removes  superfluous  fruit -buds;  allow 
more  thorough  spraying;  increases  ease  of 
access  into  the  tree  by  the  pickers.  Prun- 
ing also  keeps  plants  within  bounds,  and  ^ 
Corrects  misshapen  or  awkward  forms. 

130.  The  first  pruning  is  performed 
when  the  plant  is  set  or  planted.  The 
broken  and  dead  roots  are  removed,  and 
part  of  the  top  is  taken  away.  There 
should  be  a  -proper  balance  between  root 

(59) 


)l.  Showij 

gin 

>\V    III 

icl 

the  leave 

9  or 

top 

)f  a 

young    pi 
removed 
planting. 

Hit 

may 
tri 

be 
ns- 

2.  Suggestions  for 
pruning  rout  and  tup 
of  an  apple  tree  »  hell 
ii  i-  i ransplanted.  A 
pruned  top  ifl  shown 
at  a. 


60 


PRUNING 


and  top,  when  a  tree  is  dislodged  from  the  earth  and  taken 
to  another  place.  We  have  found  that  the  leaves  of  cuttings 
are  sometimes  reduced  for  a  similar  reason  (63).    In  most 


^f",;;,. 


103.  Peach  tree  unpruned  and  pruned. 

trees  and  shrubs   (except  conifers)  the  top  is  cut  back  as 
much  as  one-half  on  transplanting.  (Figs.  101,  102.) 

131.  Young  trees  may  be  so  pruned  that  so  many  branches 
will  not  grow  as  to  confuse  and  crowd  the  tree-top  later  on. 
A  few  framework  or  scaffold  branches  should  be  left.  (Fig. 
103.)  An  effort  should  be  made  to  shape  the  tree  sym- 
metrically; and  if  the  trees  are  to  constitute  an  orchard, 
they  should  be  uniform  in  shape  and  height  of  top.  (Figs. 
104,  105.)    "As  the  twig  is  bent  the  tree's  inclined." 

132.  Fruit 
plants  should  be 
so  pruned  as  to 
encourage  and 
spare  sufficient 
bearing  wood  to 
insure  a  good 
crop.  We  have 
identified  the 
fruit-buds  (Chap- 
ter VII).  The 
strongest  and  best 

States  and  Canada,  apple  trees  are  usually  trained  lower  ,  ■,        ,  ■, 

than  this,  to  shield  the  trunks.  Placea        DUC1S 


k-.:: 


HOW    TO    PRUNE 


(il 


105.  Well-formed  peach  trees  in  the  eastern  region. 


should  be  saved.    Thinning  the  fruit-buds  thins  the  fruit. 
In  some  fruit  plants,  the  bearing  wood  is  on  canes  that  live 

or  that  bear  for 
a  single  year 
only.  Of  such 
are  blackberries 
and  raspberries. 
The  raspberry 
cane  that  springs 
from  the  root 
this  year,  bears 
fruit  next  year, 
and  then  dies  or 
becomes  so  weak 
as  to  be  worth- 
less; and  the 
cane  that  comes 
up  next  year  bears  fruit  the  year  after,  thus  maintaining  the 
succession.  Therefore,  every  fall  or  spring  the  canes  that 
have  borne  should  be  cut  away  near  the  ground;  a  certain 
number  (four  to  eight)  of  the  new  ones  should  be  allowed  to 
remain;  and  these  new  ones  are  later  cut  back  to  make  them 
upright  and  to  concentrate  the  bearing  area.  (Figs.  106,  107.) 
133.  Shrubs  and  trees  grown  for  bloom  may  bear  their 
flowers  from  winter  or  resting  buds,  or  from  growing  shoots 
of  the  season;  if  the  former,  they  bloom  very  early  in 
spring,  as  lilac,  flowering  almond,  deutzia,  weigela,  for- 
sythia  or  golden  bell;  if  the  latter,  they  bloom  later  after 
active  twig  growth  begins,  as  rose  of  sharon  or  hibiscus, 
hydrangea,  privet,  mock  orange,  rose  acacia,  most  honey- 
suckles. If  it  is  desired  not  to  remove  (he  bloom,  those 
bushes  that  bloom  from  resting  buds  should  be  pruned 
or  headed  back  (if  at  all)  after  flowering  or  when  in  leaf: 
the  other  class  should  be  pruned  before  flowering,  or  when 
the  plant  is  dormant. 


62 


PRUNING 


134.  Pruning  is  sometimes  employed  to  increase  the  vigor 
of  weak  or  injured  plants,  and  to  renew  and  reshape  old  trees. 
Woody  plants  severely  injured  by  frost  are  often  cut  back 


106.  Raspberry  before  pruning. 


107.  Same  bush  after  the 
spring  pruning. 


heavily  to  fresh  clean  wood.  (Fig.  108.)  The  vigor  of  the 
plant  is  condensed  into  a  smaller  area,  new  shoots  arise,  and 
a  renewed  top  may  be  formed. 

135.  In  pruning,  all  long  stubs  should  be  avoided,  and 
the  cut  should  be  smooth  and  not  splintered.  The  "healing" 
of  such  a  wound  is  merely  the  covering  of  the  stub  or  cut 
area  by  a  callus  or  ring  of  tissue  that  arises  from  the  cambium 
region  (between  wood  and  bark);  this  callus  does  not  form 

readily  on  long 
and  leafless 
stubs.  An  un- 
covered wound 
tends  to  rot,  and 
a  hole  is  formed 
into  the  tree. 
Figs.  109  and  110 
show  poor  and 
good  pruning. 
The  limb  should 


108.  Peach  trees  heavily  cut  back  after  a  freeze. 


HOW    THE    LIMBS    ARE    TO    BE    CUT 


63 


be  severed  practically  parallel  to  its  parent  branch  and  close 
to  it.  Some  of  the  worst  examples  of  pruning  (or  of  tree 
butchery)  are  to  be  found  along  streets  where  trees  have 
been  cut  to  allow  the  passage  of  telephone  and  telegraph 
wires  and  other  improvements.  Only  careful  and  practiced 
persons  should  be  allowed  to  prune  street  trees. 

136.  Pruning  may  be  performed  at  any  time  of  the  year, 
depending  on  the  climate  and  the  objects  to  be  attained. 
Fruit  trees  and  shade  trees  are  usually  pruned  in  spring, 
before  the  leaves  appear.  Sometimes  the  heading  in  of  fruit 
trees  is  performed  in  late  summer  or  fall,  but  late  winter  and 
spring  pruning  for  all  trees  is  most  favored  in  cold  climates. 


109.  Poor  pruning 


110.   Good  pruning. 


Review. — What  do  you  understand  by  pruning?  What  does  prun- 
ing accomplish?  Is  it  "unnatural"?  How  should  newly  set  trees  and 
plants  be  pruned?  Why?  What  relation  has  pruning  to  the  bearing 
wood?  What  are  the  considerations  in  the  pruning  of  flowering  shrubs'.' 
What  kind  of  pruning  is  practised  on  weak  or  injured  plants?  How 
should  the  pruning  wounds  be  made?  How  do  wounds  heal'.'  When 
may  pruning  be  performed?  How  would  you  prune  a  bearing  apple 
tree  (ask  some  one  who  knows)?    A  raspberry  or  blackberry  bush? 


CHAPTER  XI 

THE   FORMS    OF   PLANTS 

137.  Although  the  form  of  the'  branch,  and  to  some 
extent  the  entire  plant,  is  determined  by  a  struggle  with 
the  conditions  in  which  it  grows,  nevertheless  each  kind 
of  plant  has  its  own  peculiar  habit  of  growth.    The  lum- 


111.   Different  forms  of  trees. 

berman  distinguishes  the  kinds  of  trees  by  their  "looks," 

rather  than  by  their  leaves  or  flowers,  as  the  botanist  does. 

The  farmer  usually  does  the  same  with  his  cultivated  plants. 
138.  The  habit   of  a  plant  is   determined  by   its  size, 

general  style  or  direction  of  growth,  form  of  head,  and  method 
of  branching.  The  general  style  or  stature 
of  plants  has  been  mentioned  in  Chapter 
III — they  may  be  erect,  strict,  creeping, 
decumbent,  and  the  like.  The  shape  of 
the  top  or  head  is  well  illustrated  in  trees. 
Note  the  general  effect  of  the  mass,  as 
seen  at  a  distance.  The  elm  is  vase-form 
or  round-headed.  (Fig.  111.)  So  are  maple, 
beech,  and  apple  trees.  The  Lombardy 
poplar  (Fig.  112)  is  columnar  or  fastigiate. 
Young  spruces  and  firs  are  conical. 
(64) 


k 


112.   Round-headed  and 
fastigiate  trees. 


THE    TREE    TOPS 


65 


Heads  may  be  narrow, 
wide,  flat,  symmetrical, 
irregular  or  broken. 

139.  The  general  leaf- 
age or  furnishing  of  the 
top  is  different  for  each 
kind.  The  top  may  be 
dense  or  thin.  The  foliage 
may  be  heavy,  light,  large, 
small.  Compare  maples 
and  elms,  apples  and 
peaches,  and  other  trees. 

140.  The  trunk  or  bole 
of  the  tree  is  one  of  its 
most  conspicuous  fea- 
tures.   Observe  the  strict 

ii3.  The  unbranched  trunk,  of  palms.  straight    trunk    of    the 

palm  (Fig.  113),  and  the  forking  trunk  of  elms  and  maples. 
Observe  that  no  two  trees  have  trunks  quite  alike.  The  bark 
is  different  for  each  kind  of  plant. 


114.  The  plant  form  in  winter.- 


%& 


*£§&&: 


i 

is 


j£P» 


-Russian  thistle. 


15.   A  plant  form. — Cotton. 


141.  Plants  awaken  certain  thoughts  or  feelings:  they 
are  said  to  have  expression.  This  expression  is  the  source 
of  much  of  our  pleasure  in  them.  Trees  are  particularly 
expressive.     One  suggests  restfulness,  because  of  its  deep, 


66 


THE    FORMS   OF   PLANTS 


shady  top;  another  gaiety,  from  its  moving,  small,  light- 
colored  leaves;  another  heaviness,  from  its  very  large,  dull 
foliage;  another  strength,  from  the  massive  branches;  another 
grace,  from  the  flowing  outline  or  flexile  growth.  We  think 
of  the  oak  as  strong,  the  willow  as  lithe,  the  aspen  as  weak, 


116.  The  many  trunks  of  an  old  olive  tree.    Italy. 

and  the  like.  Irregular  or  gnarly  trees  suggest  struggle. 
If  all  plants,  or  even  all  trees,  were  alike,  we  should  have 
little  pleasure  in  them. 

142.  The  expression  of  a  plant  depends  to  some  extent 
on  the  character  of  the  shadows  in  the  top.  These  shadows 
(or  lights  and  shades)  are  best  seen  by  looking  at  the  plant 


THE    INTEREST    IN    PLANT    FORMS 


67 


when  the  sun  is  low  and  behind  the  observer.  Stand  at 
some  distance.  Look  at  the  dark  places  in  the  old  pasture 
maple:  they  are  lumpy  and  irregular.  In  the  pasture  beech 
they  are  in  layers  or  strata.  The  shadows  depend  mostly 
on  the  method  of  branching.  Those  who  take  photographs 
know  how  the  "high  lights"  and 
shadows  develop  on  the  plate. 
(Fig.  117.) 

143.  The  habit  of  a  plant  is 
usually  most  apparent  when  it  is 
leafless.  The  framework  is  then 
revealed.  Woody  plants  are  as 
interesting  in  winter  as  in  sum- 
mer. Observe  their  forms  as  out- 
lined against  the  sky — every  one 
different  from  every  other.  Notice 
the  plant  forms  as  they  stand  in 
the  snow.  (Fig.  114.)  Compare 
this  form  with  that  of  the  cotton 
in  Fig.  115;  or  with  that  of  any 
other  plant.  How  do  stems  of 
the  pigweed  differ  from  those  of  burdock  and  grasses? 
Observe  how  the  different  plants  hold  snow  and  ice. 

144.  The  more  unusual  the  shape  of  any  tree  or  other 
plant,  the  greater  is  our  interest  in  it,  because  our  curiosity 
is  awakened.  Some  unusual  circumstance  or  condition 
has  produced  the  abnormal  form.  Such  plants  should  be 
preserved  whenever  possible.    (Fig.  11G.) 

Review. — What  do  you  mean  by  the  statement  that  each  kind  of 
plant  has  its  own  habit  (36)?  How  do  plants  differ  in  habit?  Name 
some  of  the  forms  of  tree-tops.  How  may  plants  differ  in  the  furnish- 
ing of  the  top?  Is  the  trunk  characteristic?  Hark'.'  Bring  in  and 
describe  the  hark  of  three  kinds  of  trees.  What  is  the  expression  of 
a  tree?  Name  some  of  the  expressions?  Explain  what  you  under- 
stand by  the  shadows  in  the  top.  On  what  do  the  shadows  chiefly 
depend?  What  is  there  to  see  in  plants  in  winter?  Why  are  we  interested 


117.  The  lights  and  shades. — Honey 
locust  tree. 


68 


THE    FORMS   OF   PLANTS 


in  plants  of  unusual  form?  Tell  how  any  two  trees  differ  in  "looks." 
Note. — One  of  the  first  things  the  pupil  should  learn  about  plants 
is  to  see  them  as  a  whole.  He  should  get  the  feeling  of  mass.  Then 
he  should  endeavor  to  determine  why  the  mass  is  so  and  so.  Trees 
are  best  to  begin  on.  No  two  trees  are  alike.  How  do  they  differ? 
The  pupil  can  observe  as  he  comes  and  goes  from  school.  An  orchard 
of  different  kinds  of  fruits  shows  strong  contrasts.  Even  different 
varieties  of  the  same  fruit  may  be  unlike  in  habit.  This  is  especially 
true  in  pears  (Figs.  118,  119).  It  is  well,  also,  to  develop  the  feeling 
for  the  mass,  and  to  apprehend  the  expression,  in  a  field  of  wheat  or  of 
clover,  a  field  of  potatoes,  an  apple  orchard,  a  vegetable  garden:  dis- 
tinguish the  various  plant  forms  and  also  the  impression  that  the 
entire  field  or  garden  or  woodland  makes  on  you. 


1 18.  A  young  pear  tree  of  the  Kieffer 
variety. 


119.  A  pear  tree  of  the  Hardy 
variety. 


CHAPTER   XII 

WATER   AND   MINERAL   NUTRIENTS.— ROOT   ACTION 

145.  Plant-food. — Having  learned  what  a  plant  is  and 
having  seen  it  as  a  whole,  we  may  now  inquire  how  it  secures 
food  with  which  to  live.  We  can  discuss  only  the  outlines 
of  the  subject  here:  the  pupil  may  consider  the  question 
again  when  he  takes  up  Part  III.  The  plant  secures  water 
and  mineral  nutrients  from  the  soil.  It  also  takes  up  mineral 
elements  which  are  not  nutrients,  but  which  enter  the  plant 
because  they  are  in  solution  in  the  soil-water.  The  word 
plant-food  is  used  commonly  to  include  the  water  and 
mineral  nutrients  taken  in  by  the  roots.  Technically,  the 
word  plant-food  is  used  to  designate  such  products  as 
starch,  sugar,  fats  and  other  substances  elaborated  by 
the  plant.  The  latter  usage  is  unfortunate,  but  we  shall 
follow  it  here,  according  to  botanical  usage,  to  avoid 
confusion.  ,.         a^ 

146.  Root  Structure.  — Roots  divide  &LlJ80% 
into  the  thinnest  and  finest  fibrils:  there  fi 
are  roots  and  there  are  rootlets.  The  large, 
fleshy  root  of  the  radish  (Fig.  120)  ter- 
minates in  a  common-sized  root  to  which 
little  rootlets  are  attached.  There  are 
also  little  rootlets  attached  to  the  fleshy 
root  at  various  places  near  the  base.  But 
the  rootlets  that  we  see  are  only  inter- 
mediary, and  there  are  numerous  yet 
smaller  structures. 

147.  The  rootlets,  or  fine  divisions,  are  clothed  with 
root-hairs  (29),  which  are  very  delicate  structures.   Carefully 

(69) 


120.    Root  ami  rootlets. 


70 


WATER    AND    MINERAL   NUTRIENTS 


germinate  radish  or  other  seed,  so  that  no  delicate  parts 
of  the  root  will  be  injured.  For  this  purpose,  place  a  few 
seeds  in  packing-moss  or  in  the  folds  of  cloth  or  blotting- 
paper,  being  careful  to  keep  them 
moist.  In  a  few  days  the  seed  has 
germinated,  and  the  root  has  grown 
an  inch  or  two  long.  Notice  that, 
excepting  at  a  distance  of  about  a 
quarter  of  an  inch  behind  the  tip, 
the  root  is  covered  with  minute 
hairs  (Figs.  11,  121).  They  are 
actually  hairs,  that  is,  root-hairs. 
Touch  them  and  they  collapse,  they 
are  so  delicate.  Dip  one  of  the  plants  in 
water;  remove  it, — the  hairs  are  not  to  be 
seen.  The  water  mats  them  together  along 
the  root  and  they  are  no  longer  evident. 
Root-hairs  usually  are  destroyed  when  a 
plant  is  pulled  out  of  the  soil,  be  it  done 
ever  so  carefully.  They  cling  to  the  minute 
particles  of  earth.  Under  a  microscope, 
observe  how  they  are  flattened  when 
they  come  in  contact  with  grains  of  sand 
(Chapter  II).  These  root-hairs  clothe  the  young  rootlets, 
and  a  great  amount  of  soil  is  thus  brought  into  actual  con- 
tact with  the  plant.  Root-hairs  are  not  young  roots:  they 
soon  die. 

148.  Rootlet  and  root-hair  differ.  The  rootlet  is  a  compact, 
cellular  structure.  The  root-hair  is  a  delicate  tube  (Fig. 
122),  within  the  cell-wall  of  which  is  contained  living  matter 
(protoplasm);  the  wall  and  the  lining  membrane  permit 
water  and  substances  in  solution  to  pass  in.  Being  long  and 
tube-like,  these  root-hairs  are  especially  suited  for  taking 
in  the  largest  quantity  of  solutions;  and  they  are  the  principal 
means  by  which  material  is  absorbed  from  the  soil,  although 


121.  Root  of  pumpkin 
seedling,  showing  the 
covering  of  root-hairs. 


WATER    ABSORPTION 


71 


the  surfaces  of  the   rootlets  themselves  do  a  small  part. 


Water-plants  probably  absorb 
through  the  leaves  and  stems. 
Most  of  the  higher  plants,  how- 
ever, growing  in  water,  are  pro- 
vided with  roots  and  root-hairs 
and  considerable  absorption  is 
effected  by  these.  Certain  of  the 
water-plants  have  roots  but 
produce  no  root-hairs;  others, 
as  the  utricularia  or  bladder- 
wort,  have  no  roots  whatever. 

149.  Osmosis. — To  under- 
stand how  water  enters  the 
root-hair,  it  is  necessary  that 
we  study 


a   great  quantity  of   water 


To  illustrate  osmosis, 


122.  Cross-section  of  root,  enlarged, 
showing  root-hairs. 


the  process  of  osmosis.  A  salt  or  sugar 
solution,  separated  from  water  by  a 
semi-permeable  membrane,  will  in- 
C  crease  its  volume,  due  to  the  passage 
into  the  solution  of  some  of  the  water. 
This  can  be  easily  demonstrated.  (Fig. 
123.)  Dissolve  in  one  pint  of  water,  one 
ounce  of  either  common  household  sail 
(sodium  chlorid)  or  saltpeter  (sodium 
nitrate).  Saltpeter  is  a  valuable  plant 
fertilizer.  Tie  securely  over  the  large 
mouth  of  the  tube  a  piece  of  animal 
membrane  (hog's  bladder  is  excellent 
for  the  purpose).  Now  fill  the  enlarged 
end  of  tube  with  either  the  common 
salt  or  the  saltpeter.  Then  sink  the 
tube,  as  in  Fig.  123,  in  the  bottle  A.  of 
water,  until  the  level  of  the  water  in  the 
tube  stands  at  the  same  height  as  that 


72  WATER   AND   MINERAL   NUTRIENTS 

in  the  bottle.  The  tube  may  be  readily  secured  in  this  position 
by  passing  it  through  a  hole  in  the  cork.  In  a  short  time,  we 
notice  that  the  liquid  in  N  begins  to  rise,  and  in  an  hour  or 
so  it  stands  at  F,  say.  The  diffusion  of  water  through  this 
membrane  into  the  salt  solution  is  known  as  osmosis.  Under 
these  conditions,  there  is  pressure  in  the  tube  and  this  pres- 
sure is  .known  as  osmotic  pressure.  We  may  have  osmosis 
taking  place  from  a  weak  solution  to  a  stronger  solution. 

150.  The  root-hairs  secure  water  from  the  soil. — The 
above  experiment  enables  us  to  understand  how  the  count- 
less little  root-hairs  act, — each  one  like  the  tube  N,  if  only 
the  whole  surface  of  the  tube  were  a  bladder  membrane,  or 
something  acting  similarly.  The  soil-water  does  not  contain 
much  of  the  soil  fertility;  that  is,  it  is  a  very  weak  solution. 
The  active  little  root-hair,  on  the  other  hand,  is  always 
filled  with  cell-sap,  a  more  concentrated  solution;  hence 
soil-water  must  come  in,  and  along  with  it  come  also  small 
quantities  of  dissolved  food  materials.  Some  of  these  ma- 
terials may  be  fertilizers  that  have  been  applied  to  the  land. 

151.  This  principle  of  absorption  of  water  by  osmosis 
may  now  be  demonstrated  by  another  experiment.  Fleshy 
pieces  of  root  or  stem  will  absorb  water  from  weak  solutions 
and  become  rigid;  in  strong  solutions  such  fleshy  parts  will 
give  up  their  water  and  become  flexible.  Cut  several  slices 
of  potato  tuber  about  one-eighth  of  an  inch  in  thickness, 
and  let  them  remain  in  the  air  half  an  hour.  Make  up  two 
solutions  of  cane-sugar:  (1)  dissolve  four  ounces  of  sugar  in 
a  quart  of  water;  (2)  dissolve  one-half  ounce  of  sugar  in  a 
quart  of  water.  Place  pieces  of  the  potato  tuber  in  these 
solutions.  In  half  an  hour  those  pieces  in  the  weak  solution 
will  be  rigid  or  stiff  (turgid);  those  in  the  strong  solution 
will  be  flexible  (flaccid).  The  potato  tuber  is  composed  of 
thousands  of  minute  cells,  each  with  a  cell  wall,  protoplasm, 
starch  grains,  and  cell-sap.  The  cell-sap  contains  sugars 
and  various  salts  in  solution.    When  the  slice  of  tuber  is 


OSMOSIS   AND    SAP-PRESSURE 


73 


placed  in  weak  sugar  solution  (each  cell  having  a  concen- 
tration greater  than  the  outside  solution),  it  takes  up  water. 
The  slices  of  tuber  in  the  strong  solution  lose  water  because 
the  concentration  of  the  external  solution  is  stronger  than 
that  of  the  cell-sap. 

152.  The  root-hairs  are  able  to  take  up  water  from  the 
soil  because  the  soil  solution  is  extremely  dilute.  If  the  soil 
solution  were  strong,  the  plant  might  give  up 
water  to  the  soil.  It  would  be  possible  to  add 
so  much  fertilizer  to  the  land  as  to  cause  the 
plant  to  lose  water  by  exosmosis.  There  is 
seldom,  however,  any  danger  that  the  farmer  or 
gardener  will  add  so  much  fertilizer  to  the  soil, 
in  practice,  as  to  cause  a  wilting  of  the  plant 
due  to  loss  of  water  by  exosmosis. 

153.  The  water  and  salts  in  solution  taken 
up  by  the  root-hairs  pass  into  the  root  proper 
and  finally  into  definite  routes  that  are  con- 
tinuous from  the  root  through  the  stems  to  the 
leaves.  To  illustrate  the  path  of  water-ascent, 
insert  a  growing  shoot  in  water  that  is  colored 
with  eosin.  (Eosin  may  be  had  of  dealers  in 
microscopic  supplies.  Common  aniline  may 
answer  very  well.)  The  tissues  stained  with 
the  dye  are  the  conducting  tissues.  In  woody 
plants,  the  water  is  conducted  in  the  young 
wood,  not  between  the  bark  and  wood 
as  commonly  supposed. 

154.  The  absorption  of  water  by  a 
root  may  be  so  rapid  as  to  give  rise  to 
distinct  pressure.  This  force  is  root-  or 
sap-pressure.  It  varies  in  different  plants 
and  in  the  same  plant  at  different  times. 
The  "bleeding"  of  plants  is  a  manifesta- 
tion of  this  pressure.    In  the  spring,  the 


124.    To  show 
sap-pressure. 


74  WATER    AND    MINERAL    NUTRIENTS 

maple  and  grape  particularly  exhibit  strong  sap-pressure.  To 
illustrate  root-pressure,  grow  squash  or  cucumber  plants,  and 
when  they  are  about  a  foot  or  more  in  height  cut  off  the 
plant  close  to  the  ground.  To  the  plant  stem  attach  a  small 
piece  of  rubber  tubing.  Fill  it  with  water  and  then  connect 
it  to  a  glass  tube.  (Fig.  124.)  At  intervals  note  the  rise  of 
water  due  to  root-pressure.  The  root-pressure  in  a  large 
cucumber  plant  may  force  sap  to  a  height  of  five  feet  or  more 
in  a  tube  of  five  millimeters  diameter. 

Review. — What  is  meant  by  plant-food?  Plant  nutrient?  De- 
scribe the  root  structure.  What  are  root-hairs?  Their  function?  How- 
do  water  plants  secure  water?  Do  they  have  roots  and  root-hairs? 
Explain  osmosis.  Exosmosis.  How  does  water  enter  the  root?  Why? 
How  can  you  illustrate  the  path  of  water-ascent?  What  is  root-  or  sap- 
pressure?  Why  do  plants  "bleed?"  Have  you  ever  actually  seen  root- 
hairs?  Explain  where  and  when.  Make  a  drawing  as  they  appeared 
to  you. 


CHAPTER   XIII 


WATER   AND    MINERAL    NUTRIENTS. 
THE   ROOT 


-ACTION    ABOVE 


155.  The  water  in  the  soil  is  not  usually  present  as  free 
water,  but  in  the  form  of  films  that  adhere  to  the  indi- 
vidual particles  of  soil.  The  root-hairs  are  in  contact  with 
the  soil  particles  and  films  of  water.  (Fig.  125.)  The  finer  the 
soil,  the  greater  the  number  of  soil-particles  and  the  greater 
the  film-moisture.  The  film-moisture  surrounding  the  grains 
may  not  be  perceptible,  yet  the  plant 
can  utilize  it.  Absorption  by  roots  may 
continue  in  a  soil  that  seems  to  be 
dust  dry. 

156.  The  root  must  be  warm  if  it  is  to 
perform  its  functions.  A  proper  tempera- 
ture is  essential  to  the  life  processes. 
Should  the  soil  of  fields  or  greenhouses 
be  much  colder  than  the  air,  the  plant 
suffers.  When  in  a  warm  atmosphere, 
or  in  a  dry  atmosphere,  plants  need  to 
absorb  much  water  from  the  soil,  and 
the  roots  must  be  warm  if  the  root-hairs 
are  to  supply  the  water  as  rapidly  as  it 
is  needed.  If  the  roots  are  chilled,  the 
plant  may  wilt  or  die.  Try  this  with  two 
potted  plants,  as  radish,  coleus,  tomato. 
Put  one  pot  in  a  dish  of  ice  water,  and 
the  other  in  a  dish  of  warm  water,  and 
keep  them  in  a  warm  room.  In  a  short 
time   notice   how  stiff  and  vigorous   is 

(75) 


125.  The  rootlets  and 
root-hairs   cling  to  the 

particles  of  soil. 


76  WATER    AND    MINERAL    NUTRIENTS 

the  one  whose  roots  are  warm,  whereas  the  other  may  show 
signs  of  wilting. 

157.  Plants  take  from  the  soil  an  immense  quantity  of 
water.  A  single  corn  plant  may  require  in  a  growing  season 
200  to  500  pounds  of  water.  From  250  to  400  or  more  pounds 
of  water  are  required  for  the  production  of  one  pound  of 
dry  matter  in  plants.  Most  of  the  water  absorbed  by  the 
roots  is  given  off  by  the  plant  as  water  vapor  in  a  process 
of  evaporation  called  transpiration  (166). 

158.  Water  serves  the  plant  in  a  number  of  ways.  It  is 
a  nutrient  for  the  plant  and  takes  part  in  the  formation  of 
substances  manufactured  by  the  plant.  The  cell  sap  is 
water  with  substances  in  solution.  The  water  serves  as  a 
carrier  of  the  materials  derived  from  the  soil  and  also 
for  the  manufactured  food  made  within  the  plant.  Let  us 
see  what  nutrients  the  ordinary  green  plants  secure  from 
the  soil. 

159.  Nutrient  Materials  Secured  from  the  Soil. — We  have 
seen  that  all  nutrient  material  must  be  in  solution  in  water 
to  be  taken  in  by  the  root.  The  ordinary  green  plant  obtains 
from  the  soil  the  following  essential  elements: 

Nitrogen,  chemical  symbol  N.  Potassium,  K. 

Phosphorus,  P.  Calcium,  Ca. 

Sulfur,  S.  Magnesium,  Mg. 
Iron,  Fe. 

Chlorin  is  also  an  essential  element  for  buckwheat.  The 
elements  in  the  above  list  (except  nitrogen)  are  known  as 
the  mineral  elements.  All  of  the  above  elements  are  taken 
up  not  in  their  elemental  form  but  in  the  form  of  salts. 

160.  Ten  elements  are  essential  for  the  growth  of  all 
green  plants.  In  addition  to  the  seven  above  mentioned,  the 
plant  requires  hydrogen,  H,  oxygen,  O,  and  carbon,  C. 
Hydrogen  and  oxygen  are  supplied  in  the  form  of  water, 
which  has  the  chemical  formula  H2O.    Carbon  for  the  green 


FERTILIZERS 


77 


plant  is  provided  in  the  carbon  dioxid  (CO2)  of  the  air.  Oxygen 
is  also  derived  from  air  (187).  When  the  plant  is  burned,  the 
six  mineral  elements  remain  in  the  ash. 

161.  The  ash  is  but  a  very  small  part  of  the  total  weight 
of  the  plant.  In  a  corn  plant  of  the  roasting-ear  stage,  the 
ash  (what  remains  after  ordinary  burning)  is  about  one  per 
cent  of  the  total  substance.  A  good  wheat  crop  will  require 
per  acre  about  ten  pounds  of  phosphoric  acid  and  about 
thirty  pounds  of  potash.  The  amount  of  phosphoric  acid 
removed    by    200    bushels    of 

potatoes  is  nine   pounds;   and 
of  potash  sixty  pounds. 

162.  The  farmer  does  not 
add  all  the  elements  to  the  soil 
in  the  shape  of  fertilizers.  Some 
of  the  nutrient  elements  are 
used  in  such  small  quantities 
and  are  present  in  the  soil  to 
such  an  amount  that  the  ad- 
dition of  them  is  not  necessary. 
The  farmer  adds  nitrogen,  pot- 
ash and  phosphorus  to  the  land 
to  provide  nutrients,  and  he 
also  adds  calcium  in  lime  or 
land-plaster  because  of  its 
chemical  and  physical  effect  on 
the  soil.  Some  of  the  fertilizers 
are  mined,  others  are  by-pro- 
ducts Of  packing-houses  and  126.  Nodules  on  soybean, 
other  manufacturing  establishments.  Stable  manure  is  gen- 
erally considered  to  be  the  best  single  fertilizer. 

163.  Nitrogen  is  one  of  the  most  essential  elements 
required  by  the  plant.  It  is  expensive  to  add  to  the  soil  as 
fertilizer.  Fortunately,  nature  has  provided  a  method 
whereby  some  of  the  inexhaustible  nitrogen  supply  of  the 


ntk 

fi  1 

^wk 

I  ^fl^a 

lTmL 

\m 

-'/ 

\L-~P 

78 


WATER    AND    MINERAL    NUTRIENTS 


air  is  taken  into  the  soil.  Dig  up  a  clover,  vetch,  pea,  bean, 
cowpea,  alfalfa  or  other  legume  plant.  Carefully  wash  the 
soil  away  from  the  roots.  Nodule  swellings  will  probably 
be  found  on  the  roots.  (Figs. 
126, 127.)  In  these  nodules  are 
certain  bacteria  that  secure 
nitrogen  from  the  air,  and  from 
which  they  build  up  more 
complex  nitrogenous  com- 
pounds. The  legume  host-plant 
then  appropriates  some  of  the 
nitrogen  fixed  by  bacteria  and 
the  remainder,  of  course,  re- 
mains in  the  bacteria. 

164.  Only  the  leguminous 
plants  bear  these  nodules. 
The  legumes  are  plants  of  the 
great  family  Leguminosse, 
comprising  all  pea-like,  bean- 
like, clover-like,  acacia-like  and 
other  pod-bearing  plants.  It 
has  been  demonstrated  that 
over  100  pounds  of  nitrogen 
per  acre  can  be  fixed  by  these 
nodule-forming  bacteria  dur- 
ing a  growing  season.  These 
bacteria  are  not  present  in  all 
fields.  They  must  be  intro- 
duced to  fields  on  which 
legumes  have  not  grown. 
Moreover,  the    bacteria    that 

127.  Nodule,  on  root  of  Canada  field  pea.     j^^  the  df  ajf  &  wiU  not  j^^ 

the  cowpea.  A  different  "strain"  or  variety  is  necessary  for 
almost  every  legume.  So  important  are  the  bacteria  that 
the  farmer  who  desires  to  enrich  his  soil  and  secure  good 


SOIL   NUTRIENTS  79 

crops  introduces  these  bacteria  into  his  field  by  the  appli- 
cation of  soil  taken  from  a  field  known  to  have  them,  or 
possibly  in  some  cases  he  introduces  the  bacteria  by  the  use 
of  commercial  cultures.  Certain  legume  crops,  as  alfalfa,  will 
do  poorly  unless  the  bacteria  are  present. 

165.  A  simple  experiment  will  demonstrate  the  growth 
of  plants  in  a  nutrient  solution,  such  as  may  exist  in  the 
soil.  Secure  from  the  druggist  the  following  chemicals  and 
make  a  solution  of  them,  using  the  amounts  here  indicated: 

Potassium  nitrate,  KNO3   2  grains 

Calcium  phosphate,  monobasic,  CaH4(P04)2 1  grain 

Or  Calcium  phosphate  dibasic  Ca2H2(PO\j)2 1  grain 

Magnesium  sulfate,  MgS04 0.50  grain 

Ferric  chloride,  very  slight  trace. 

Water  (distilled) 5  quarts 

Fill  four  or  five  tumblers  with  this  solution  and  cover 
the  tumblers  with  paraffined  paper.  Germinate  peas  or  seeds 
of  a  similar  plant,  and  when  the  roots  are  two  inches  long 
punch  holes  in  the  paper  and  insert  the  roots  through  the 
holes  into  the  nutrient  solution.  Place  the  cultures  in  good 
light  and  allow  the  seedlings  to  grow  three  or  four  weeks. 
For  comparison,  grow  some  of  the  plants  in  distilled  water 
in  place  of  the  nutrient  solution. 

166.  Transpiration. — We  have  found  that  the  plant 
takes  nutrients  from  the  soil  in  very  dilute  solutions.  Much 
more  water  is  absorbed  by  the  roots  than  is  used  in  growth, 
and  this  surplus  water  is  given  off  from  the  leaves  into  the 
atmosphere  by  the  evaporation  process  known  as  trans- 
piration (157).  The  transpiration  takes  place  more  abun- 
dantly from  the  under  surfaces  of  leaves  in  most  plants, 
and  through  the  pores  or  stomates.  It  has  been  found  that  a 
sunflower  plant  of  the  height  of  a  man,  during  an  active 
period  of  growth,  gives  off  more  than  a  quart  of  water  per 
day.    A  large  oak  tree  may  transpire  150  gallons  per  day 


80 


WATER     AND     MINERAL     NUTRIENTS 


during  the  summer.  For  every  ounce  of  dry  matter  pro- 
duced, it  is  estimated  that  fifteen  to  twenty-five  pounds 
of  water  must  pass  through  the  plant.  Cut  off  a  succulent 
shoot  of  any  plant,  press  the  end  of  it  through  a  hole  in  a  cork 

and  stand  it  in 
a  small  bottle  of 
water.  Invert 
over  this  bottle 
a  large-mouthed 
bottle  (as  a  fruit- 
jar),  and  notice 
that  a  mist  soon 
accumulates  on 
the  inside  of  the 
glass.  In  time, 
drops  of  water 
form.  The  ex- 
periment may  be 
varied  as  shown 
in  Fig.  128.  Or 
invert  the  fruit- 
jar  over  an  entire 
plant,  as  shown 

128.  To  illustrate  transpiration.  •       p-         inq    tak- 

ing care  to  cover  the  earth  with  oiled  paper  or  rubber  cloth 
to  prevent  evaporation. 

167.  Even  in  winter,  moisture  is  given  off  by  leafless 
twigs.  Cut  a  twig,  seal  the  severed  end  with  wax,  and  allow 
the  twig  to  lie  several  days :  it  shrivels..  There  must  be  some 
upward  movement  of  water  even  in  winter,  else  plants  would 
shrivel  and  die. 

168.  When  the  roots  fail  to  supply  to  the  plant  sufficient 
water  to  equalize  that  transpired  by  the  leaves,  the  plant 
wilts.  Transpiration  from  the  leaves  and  delicate  shoots  is 
increased  by  all  of  the  conditions  that  increase  evaporation, 


w&k. .;'  ■^■^''^?4 

M 

''■'■■"■>'Bf  ■■ 

-'■  —  '';*■•  Blii'lir 

itni^^'liil'  1 

WHY    PLANTS    WILT 


81 


as  higher  temperature,  dry  air  or  wind.  In  especially  hot 
weather,  when  the  wind  is  brisk  and  the  air  dry,  the  roots 
may  be  very  active  and  yet  fail  to  absorb  sufficient  moisture 
to  equalize  that  given  off  by  the  leaves.  Any  injury  to  the 
roots  or  even  chilling  them  (156) 
may  cause  the  plant  to  wilt.  On  a 
hot,  dry  day,  note  how  the  leaves 
of  corn  "roll"  toward  afternoon. 
Early  the  following  morning,  note 
how  fresh  and  vigorous  the  same 
leaves  appear.  Water  is  also  forced 
up  by  root-pressure  (154).  Some  of 
the  dew  on  the  grass  in  the  morn- 
ing may  be  the  water  forced  up  by 
the  roots;  some  of  it  is  the  condensed 
vapor  of  the  air. 

169.  The  wilting  of  a  plant  is  due 
to  the  loss  of  water  from  the  cells. 
The  cell  walls  are  soft,  and  they  col- 
lapse. A  toy  balloon  will  not  stand  alone  until  it  is  inflated 
with  air  or  liquid.  In  the  woody  parts  of  the  plant  the  cell 
walls  may  be  stiff  enough  to  support  themselves,  even  though 
the  cell  is  empty.  Measure  the  contraction  due  to  wilting 
and  drying  by  tracing  a  fresh  leaf,  and  then  tracing  the 
same  leaf  after  it  has  been  dried  between  papers.  The 
softer  the  leaf,  the  greater  will  be  the  contraction. 

Review. — What  relation  do  root-hairs  have  to  soil-particles?  What 
is  the  effect  of  the  chilling  of  roots?  Of  what  use  to  the  plant  is  water'.' 
What  essential  elements  are  taken  from  the  soil?  How  many  elements 
are  essential  for  the  plant?  What  is  the  ash?  What  elements  does  the 
fanner  add  as  fertilizers?  How  may  the  nitrogen  supply  of  the  soil  be 
increased?  What  plants  possess  the  root  nodules?  What  is  soil 
inoculation?   What  is  transpiration?   When  does  a  plant  wilt? 


129.  To  illustrate  transpiration. 


CHAPTER    XIV 

FOOD   ELABORATION   AND   RESPIRATION 

170.  Sources  of  Raw  Material. — The  ordinary  green  plant, 
as  we  have  seen,  secures  water  and  certain,  substances  from 
the  soil.  It  also  secures  from  the  air  raw  material  which  it 
utilizes  in  the  elaboration  of  food  material.  When  a  plant  is 
thoroughly  dried  in  an  oven,  the  water  passes  off;  this  water 
came  from  the  soil.  The  remaining  part  is  called  dry  sub- 
stance or  dry  matter.  If  the  dry  matter  is  burned  in  an  ordi- 
nary fire,  only  the  ash  remains;  this  ash  came  from  the  soil. 
The  part  that  passed  off  as  a  gas  in  the  burning  contained 
the  elements  that  came  from  the  air.  It  also  contained 
some  of  those  that  came  from  the  soil — all  those  (as  nitrogen, 
hydrogen,  chlorin)  that  are  transformed  into  gases  by  the 
heat  of  a  common  fire. 

171.  Carbon. — Carbon  enters  abundantly  into  the  com- 
position of  all  plants.  Note  what  happens  when  a  plant 
is  burned  without  free  access  of  air,  or  smothered,  as  in  a 
charcoal  pit.  A  mass  of  charcoal  remains,  almost  as  large 
as  the  body  of  the  plant.  Charcoal  is  almost  pure  carbon, 
the  ash  being  so  small  in  proportion  to  the  large  amount 
of  carbon  that  we  look  on  it  as  an  impurity.  Half  or  more 
of  the  dry  substance  of  a  tree  is  carbon.  The  carbon  goes 
off  as  a  gas  when  the  plant  is  burned  in  air.  It  does  not  go 
off  alone,  but  in  combination  with  oxygen,  and  in  the  form 
called  carbon  dioxid  gas,  C02. 

172.  The  green  plant  secures  its  carbon  from  the  air. 
In  other  words,  much  of  the  solid  matter  of  the  plant  comes 
from  one  of  the  gases.  By  volume,  carbon  dioxid  forms 
only  about  three-hundredths  of  1  per  cent  of  the  air.    It 

(82) 


CARBON    AND    CHLOROPHYLL  83 

would  be  very  disastrous  to  animal  life,  however,  if  this 
small  percentage  were  much  increased,  for  it  excludes  the 
life-giving  oxygen.  Carbon  dioxid  is  often  called  "foul- 
gas."  It  may  accumulate  in  old  wells,  and  an  experienced 
person  will  not  descend  into  such  wells  until  they  have  been 
tested  with  a  torch.  If  the  air  in  the  well  will  not  support 
combustion,  that  is,  if  the  torch  is  extinguished,  it  usually 
means  that  carbon  dioxid  has  drained  into  the  place.  The 
air  of  a  closed  schoolroom  often  contains  far  too  much 
of  this  gas  along  with  little  solid  particles  of  waste  matters. 
Carbon  dioxid  is  often  known  as  carbonic  acid  gas. 

173.  Appropriation  of  the  Carbon. — The  carbon  dioxid 
of  the  air  readily  diffuses  into  the  leaves  and  other  green 
parts  of  the  plant.  The  leaf  may  be  delicate  in  texture,  and 
air  may  diffuse  directly  into  the  leaf-tissues.  There  are,  how- 
ever, special  inlets  adapted  for  the  admission  of  gases  into 
the  leaves  and  other  green  parts.  These  inlets  consist  of 
numerous  pores  (stomates  or  stomata),  which  are  especially 
abundant  on  the  under  surface  of  the  leaf.  They  may  also 
be  present  on  the  upper  surface.  The  apple  leaf  contains 
about  one  hundred  thousand  of  these  pores  to  each  square 
inch  of  the  under  surface.  Through  these  pores  the  outside  air 
enters  into  the  air-spaces  of  the  plant,  and  finally  into  the 
little  cells  containing  the  living  matter.  In  Chapter  XL 
these  stomata  will  be  studied. 

174.  Chlorophyll. — The  green  color  of  leaves  is  due  to  a 
substance  called  chlorophyll.  Purchase  at  the  drug  store 
about  a  gill  of  (grain)  alcohol.  Secure  a  leaf  of  geranium,  clover, 
or  other  plant  that  has  been  exposed  to  sunlight  for  a  few 
hours  and,  after  dipping  it  for  a  minute  in  boiling  water, 
put  it  in  a  white  cup  with  sufficient  alcohol  to  cover  the 
leaf.  Place  the  cup  on  the  stove  where  it  is  not  hot  enough 
for  the  alcohol  to  take  fire.  After  a  time  the  chlorophyll  is 
dissolved  by  the  alcohol,  which  has  become  an  intense 
green.     Save  this  leaf  for  a  future  experiment.     Without 


84  FOOD    ELABORATION     AND    RESPIRATION 

chlorophyll,  the  plant  can  not  appropriate  the  carbon  di- 
oxid  of  the  air. 

175.  In  most  plants,  this  chlorophyll  or  leaf-green  is 
scattered  throughout  the  green  tissues  in  little  oval  bodies, 
and  these  bodies  are  most  abundant  near  the  upper  surface 
of  the  leaf,  where  they  secure  a  large  amount  of  light.  With- 
out this  green  coloring  matter,  there  would  be  no  reason  for 
the  large  flat  surfaces  that  leaves  possess,  and  no  reason  for 
the  fact  that  the  leaves  are  borne  most  abundantly  at  the 
ends  of  the  branches,  where  the  light  is  most  available. 
Plants  with  colored  leaves,  as  coleus,  have  chlorophyll,  but 
it  is  masked  by  other  coloring  matter.  'This  other  coloring 
matter  is  usually  soluble  in  hot  water.  Boil  a  coleus  leaf  and 
notice  that  it  becomes  green  and  the  water  becomes  colored. 

176.  Plants  grown  in  darkness  are  yellow  and  slender, 
and  do  not  reach  maturity.  Compare  the  potato  sprouts 
that  have  grown  from  a  tuber  lying  in  the  dark  cellar  with 
those  that  have  grown  normally  in  the  bright  light  (Fig. 
45).  The  shoots  have  elongated  until  the  food  which  is 
stored  in  the  tuber  is  exhausted.  These  shoots  have  lived 
useless  lives.  A  plant  that  has  been  grown  in  darkness 
from  the  seed  will  soon  die,  although  for  a  time  the  little 
seedling  will  grow  very  tall  and  slender.  Light  induces  the 
production  of  chlorophyll.  Sometimes  chlorophyll  is  found 
in  buds  and  seeds,  but  it  is  probable  in  most  cases  that 
these  places  are  not  perfectly  dark.  Notice  how  potato  tubers 
develop  chlorophyll,  or  become  green,  when  exposed  to  light. 

177.  Photosynthesis. — Carbon  dioxid  diffuses  into  the 
leaf  (173)  and  is  used  during  sunlight,  and  oxygen  is  given 
off.  We  have  seen  (172)  that  carbon  dioxid  will  not  support 
animal  life.  Experiments  show  that  carbon  dioxid  is  absorbed 
and  that  oxygen  is  given  off  by  all  green  surfaces  in  the  hours 
of  sunlight.  How  the  carbon  dioxid  may  be  used  in  making 
organic  food  is  a  complex  question  and  need  be  considered 
here  only  in  a  general  way. 


PHOTOSYNTHESIS  85 

178.  Chlorophyll  absorbs  certain  of  the  sun's  rays  and 
the  energy  thus  derived  is  used  in  uniting  the  carbon  dioxid 
with  some  of  the  water  brought  up  from  the  roots.  The 
process  is  complex,  with  some  kind  of  sugar  or  starch  as 
the  ultimate  product.  Glucose  is  probably  the  first  carbo- 
hydrate formed.  In  most  plants,  the  first  visible  product  is 
starch.  Certain  plants  do  not  produce  starch.  The  common 
onion,  amaryllis  and  iris  are  of  this  class.  The  process  of 
using  the  carbon  dioxid  of  the  air  has  been  known  as  carbon- 
assimilation,  but  the  term  now  commonly  used  is  photo- 
synthesis (from  Greek  words,  meaning  "light"  and  "put 
together"). 

179.  Glucose  or  grape  sugar  is  composed  of  carbon,  hydro- 
gen, and  oxygen  (CeHi206).  Starch  is  likewise  composed 
of  carbon,  hydrogen,  and  oxygen,  but  differs  in  the  percent- 
ages. Its  chemical  formula  is  generally  given  (C6Hio05). 
Cane  sugar,  malt  sugar,  woody  substances  are  very  similar 
in  composition.  They  are  called  carbohydrates.  In  making 
the  glucose  sugar  from  the  carbon  dioxid  and  water,  the 
oxygen  gas  is  given  off  by  the  plant  as  a  waste  product. 
The  general  chemical  formula  for  the  process  is:  6C02  + 
6H20  =  C6Hi,06+602. 

180.  In  the  daytime  the  plant,  therefore,  takes  in  carbon 
dioxid  and  gives  off  oxygen.  It  is  not  so  easy  to  demonstrate 
this  fact.  Chemical  analysis  is  the  only  way  of  proving  it. 
The  escape  of  oxygen  can  best  be  demonstrated  by  employ- 
ing water  plants.  Make  an  experiment  as  illustrated  in  Fig. 
130.  Under  a  funnel  in  a  deep  glass  jar  containing  fresh 
spring  or  stream  water,  place  fresh  pieces  of  the  common 
water-weed,  elodea  (or  anacharis).  In  sunlight,  bubbles  of 
oxygen  will  arise  and  collect  in  the  test-tube.  Some  of  the 
bubbles  may  be  only  air,  particularly  if  marked  changes  in 
the  temperature  of  the  water  occur.  A  simple  experiment  is 
to  immerse  a  stem  of  elodea  in  a  test-tube  of  water  and  hold 
the  tube  in  bright  sunlight.    Bubbles  of  gas  will  arise  from 


86 


FOOD     ELABORATION     AND     RESPIRATION 


the  cut  end  of  the  twig.  This  gas  has  been  found  to  be  largely 
oxygen.  The  water-plant  gets  its  carbon  dioxid  gas  from 
that  which  is  dissolved  in  the  water.  A  gas,  as  well  as  a 
solid,  may  be  dissolved  in  water.  Observe  the  bubbles  on 
pond-scums  and  water-weeds  on 
bright  day. 
181.  Starch  is  present  in  the 
green  leaves  that  have  been  ex- 
posed to  sunlight;  but  in  the  dark 
no  starch  can  be  formed  from 
carbon  dioxid  and  water.  Apply 
iodin  to  the  leaf  from  which  the 
chlorophyll  was  dissolved  in  a 
previous  experiment  (174).  Note 
that  the  leaf  is  colored  purplish 
brown  throughout.  Starch  gives 
a  blue  coloration  with  iodin. 
The  leaf  contains  starch  (76). 
Secure  a  leaf  from  a  plant 
that  has  been  in  the  darkness 
for  about  two  days.  Dissolve 
the  chlorophyll,  as  before, 
and  attempt  to  stain  this 
leaf  with  iodin.  No  purplish 
brown  color  is  produced. 
182.  Plants  or  parts  of  plants  that  have  developed  no 
chlorophyll  can  form  no  starch.  Secure  a  variegated  leaf 
of  coleus,  ribbon-grass,  geranium,  or  of  any  plant  showing 
both  white  and  green  areas.  On  a  day  of  bright  sunshine, 
test  one  of  these  leaves  by  the  alcohol  and  iodin  method 
for  the  presence  of  starch.  Observe  that  the  parts  devoid  of 
green  color  have  formed  no  starch.  However,  after  starch 
has  once  been  formed  in  the  leaves,  it  may  be  changed  into 
soluble  substances  and  removed  to  be  again  converted 
into  starch  in  other  parts  of  the  living  tissues. 


DIGESTION    AND    ASSIMILATION  87 

183.  Digestion. — The  starch  made  by  the  leaf  during  the 
daytime  is  present  in  the  form  of  insoluble  granules.  In 
order  to  be  carried  from  the  leaf  to  other  parts  of  the  plant 
for  purposes  of  storage  or  growth,  it  must  be  made  soluble. 
The  starch  of  the  leaves  at  night  is  converted  into  sugars 
by  the  action  of  enzymes,  or  ferments,  and  is  then  conveyed 
to  other  parts  of  the  plant.  This  conversion  is  a  process  of 
digestion.  It  is  much  like  the  change  of  starchy  foods  to 
sugary  foods  by  the  saliva. 

184.  After  being  changed  to  the  soluble  form,  this  material 
is  ready  to  be  used  in  growth,  either  in  the  leaf,  in  the  stem, 
or  in  the  roots.  With  other  more  complex  products  it  is 
then  distributed  throughout  all  of  the  growing  parts  of  the 
plant;  and  when  passing  down  to  the  root  it  passes  readily 
through  the  inner  bark,  in  plants  that  have  a  definite  bark. 
This  gradual  downward  diffusion  of  materials  suitable  for 
growth  through  the  inner  bark  is  the  process  referred  to 
when  the  "descent  of  sap"  is  mentioned.  Starch  and  other 
products  are  often  stored  in  one  growing  season  to  be  used 
in  the  next  season  (Chapter  VI).  If  a  tree  is  constricted  or 
strangled  by  a  wire  around  its  trunk,  the  digested  food  can- 
not readily  pass  down  and  it  is  stored  above  the  girdle,  caus- 
ing an  enlargement. 

185.  Assimilation. — The  food  from  the  air  and  the  nutrients 
from  the  soil  unite  in  the  living  tissues  (see  Photosynthesis, 
178).  The  sap  that  passes  upwards  from  the  roots  in  the 
growing  season  is  made  up  largely  of  the  soil-water  and  the 
salts  that  have  been  absorbed  in  the  diluted  solutions. 
We  have  found  that  this  upward-moving  water  is  conducted 
largely  through  certain  tubular  cells  of  the  young  wood  (153). 
These  cells  are  never  continuous  tubes  from  root  to  leaf; 
but  the  water  passes  readily  from  one  cell  to  another  in  its 
upward  course. 

186.  The  upward-moving  water  gradually  passes  t<>  the 
growing  parts,  and  it  comes  in  intimate  contact  with  the 


88  FOOD     ELABORATION     AND     RESPIRATION 

soluble  carbohydrates  and  products  of  photosynthesis.  In 
the  building-up  or  reconstructive  and  other  processes  it  is 
therefore  available.  There  is  a  series  of  changes,  gradually 
increasing  in  complexity.  There  are  formed  substances 
containing  nitrogen,  in  addition  to  carbon,  hydrogen  and 
oxygen.  Others  will  contain  also  sulfur  and  phosphorus,  and 
the  process  may  be  thought  of  as  culminating  in  protoplasm. 
Protoplasm  is  the  living  matter  in  plants.  It  is  in  the  cells, 
and  is  usually  semifluid.  Starch  is  not  living  matter.  The 
process  of  building  up  the  protoplasm  is  called  assimilation. 

187.  Respiration. — In  the  maintenance  and  growth  of 
the  plant,  energy  is  required.  This  energy  is  derived  from 
the  food  that  the  plant  has  manufactured;  and  its  ultimate 
source  is  the  sunlight.  For  the  release  of  this  energy,  chemi- 
cal changes  are  involved  which,  require  oxygen;  as  by-r 
products,  carbon  dioxiol  gas  is  given  off  and  water  is  formed 
in  the  cells;  this  whole  process  is  respiration.  This  process 
of  respiration  is  similarin  animals.  All  animals  require  oxygen 
and  give  off  carbon  dioxid.  Likewise,  all  living  parts  of 
the  plant  must  have  a  constant  supply  of  oxygen. 

188.  In  green  plants,  at  night,  carbon  dioxid  is  given  off 
into  the  air  and  oxygen  is  taken  into  the  cells.  In  the  day- 
time, respiration  goes  on,  but  the  required  oxygen  is  derived 
from  the  supply  released  in  photosynthesis;  and  the  carbon 
dioxid  released  in  respiration  supplies  a  part  of  the  carbon 
dioxid  used  in  photosynthesis.  In  the  daytime,  the  plants 
tend  to  purify  the  air  because  they  use  carbon  dioxid  and 
give  off  oxygen.  At  night,  like  animals,  they  tend  to  make 
the  air  foul  because  they  use  oxygen  and  give  off  carbon 
dioxid.  The  carbon  dioxid  given  off  by  a  few  plants  at 
night,  however,  is  so  slight  that  it  need  not  disturb  one  at  all. 

189.  The  oxygen  that  the  plants  need  may  come  into 
the  plant  through  the  stomata,  through  pores  in  the  stems  or 
trunks  of  trees,  or  it  may  diffuse  through  the  cell  walls. 
All  rapidly  growing  plants  respire  very  freely.   Germinating 


RESPIRATION  89 

seeds  especially  give  off  a  large  quantity  of  carbon  dioxid. 
In  a  wide-mouthed  bottle  place  several  hundred  germinating 
pea  seeds.  Fill  a  small  vial  with  a  filtered  concentrated 
solution  of  barium  hydrate.  Place  the  vial  in  the  bottle 
with  the  seeds.  Do  not  spill  the  solution.  Tightly  stopper  the 
wide-mouthed  bottle  and  after  several  hours  note  the  heavy, 
white  precipitate  that  forms  in  it.  As  a  check,  place  a 
similar  vial  of  barium  hydrate  solution  is  a  similar  bottle 
tightly  stoppered.  Does  a  heavy  precipitate  form?  Using 
a  piece  of  glass  tubing,  blow  air  into  a  bottle  of  barium  hy- 
drate. The  exhaled  air  is  rich  in  carbon  dioxid.  The  water 
becomes  turbid,  due  to  the  precipitate  formed  when  carbon 
dioxid  reacts  with  barium  hydrate. 

Review. — What  are  the  sources  of  the  raw  material?  What  part 
of  the  dry  matter  is  carbon?  What  percentage  of  the  air  is  carbon 
dioxid?  How  does  it  enter  the  plant?  WThat  is  chlorophyll?  What  is 
necessary  for  its  formation?  What  is  meant  by  photosynthesis?  What 
gas  is  given  off  in  photosynthesis?  What  conditions  are  necessary  for 
photosynthesis?  What  is  meant  by  digestion  of  starch?  What  is  meant 
by  assimilation?  Respiration?  When  does  it  occur?  What  gas  is  given 
off  in  the  process?  What  gas  is  required  in  the  process?  Contrast  the 
process  of  respiration  in  animals  and  plants. 


CHAPTER   XV 

DEPENDENT   PLANTS 

190.  Dependent  and  Independent  Plants. — Plants  with 
roots  and  foliage  usually  depend  on  themselves.  They 
collect  the  raw  materials  and  make  them  over  into  assimi- 
lable food.  They  are  independent.  Plants  without  green 
foliage  cannot  make  food :  they  must  have  it  made  for  them 
or  they  die.  They  are  dependent.  The 
potato  sprout  (Fig.  45)  cannot  collect 
and  elaborate  carbon  dioxid.  It  lives 
on  the  food  stored  in  the  tuber. 

191.  All  plants  with  naturally  white 
or  blanched  parts  are  dependent.  Their 
leaves  do  not  develop.  They  live  on 
organic  matter — that  which  has  been 
made  by  a  plant  or  an  animal.  The 
Indian  pipe,  aphyllon  (Fig.  131), 
beech -drop,  coral -root  (Fig.  132) 
among  flower-producing  plants,  also 
mushrooms  as  well  as  bacteria  and 
other  fungi  (Figs.  133,  134,  135)  are 
common  examples. 

192.  Saprophytes  and  Parasites. — 
A  plant  that  lives  on  dead  or  decay- 
ing matter  is  a  saprophyte.  Mush- 
rooms are  examples:  they  live  on  the 
decaying  matter  in  the  soil.  Mould  on 
bread  and  cheese  is  an  example.  Lay 
a  piece  of  moist  bread  on  a  plate  and 
invert  a  tumbler  over  it.     In  a  few 

(90) 


131.  A  parasite,  growing  in 
woods. — Aphyllon.  It  is  in 
bloom. 


SAPROPHYTES    AND    PARASITES 


91 


days  it  will  be  mouldy.  The  spores  were  in  the  air,  or  per- 
haps they  had  already  fallen  on  the  bread  but  had  not  had 
opportunity  to  grow. 

193.  Saprophytes  break  down  or  decompose  organic 
„  substances.  Chief  of  these  saprophytes  are  the 
microscopic  organisms  known  as  bacteria  (Fig. 
136).  These  innumerable  bodies  are  immersed  in 
water  or  in  animal  and  plant 
juices,  and  absorb  food  over 
their  entire  surface.  By 
breaking  down  organic  com- 
binations, they  produce  de- 
cay. Largely  through  their 
agency,  and  that  of  many 
true  but  microscopic  fungi, 
all  things  pass  into  soil  and 

gas.      Thus    are  the    bodies  Of    133-  A  mushroom,  example 
,  i-i  ,  of  a  saprophytic  plant. 

plants  and  animals  removed 
and  the  continuing  round  of  life  is  maintained. 
194.  A   plant   that   secures   its   nutrition   di- 
rectly from  a  living  plant  or  animal  is  a  parasite, 
and  the  plant  or  animal  on  which  it  lives  is  the 
host.    The  dodder  is  a  true  parasite.    So  are  the 
rusts  and  mildews  that  attack  leaves  and  shoots 
and  injure  them.    The  threads  of  the  parasitic 
fungus  usually   creep  through    the   intercellular 
spaces  in  the  leaf  or  stem  and  send  suckers  (or 
haustoria)  into  the  cells.   (Fig.  137.) 
In    some    forms    these    threads    (or 
lyphse)    penetrate    the    cells.     The 
hyphse  clog  the  air-spaces  of  'the  leaf 
and  often  plug  the  stomata,  and  they 
also  appropriate  and  disorganize  the 
cell    fluids:   thus  they  injure  or  kill 
showing  the  mycorhizas.    '    their  host.  The  mass  of  hyphse  of  a 


92 


DEPENDENT     PLANTS 


134.  The  cultivated  mushroom,  a  saprophytic  plant. 


fungus  is  called  mycelium.    Some  of  the  hyphse  finally  grow- 
out  of  the   leaf  and  produce  spores  or  reproductive    cells 

which  answer  the 
purpose  of  seeds 
in  distributing  the 
plant  (6,  Fig.  137). 
195.  The  ab- 
normal condition 
produced  in  plants 
by  fungous  and 
bacterial  parasites 
and  by  other  agents 
is  known  as  a  dis- 
ease. On  some 
plants,  the  disease  takes  the  form  of  a  leaf-spot  or  a  blight; 
in  others  swellings  or  galls  are  produced.  Cankers  on  branches 
of  trees  and  on  stems  of  herbaceous  plants  are  produced 
by  fungi  living  in  the  affected  tissue.  The  well-known  fire- 
blight  and  blight-canker 
of  pears  are  caused  by 
bacteria.  The  rots  of 
fruits  and  vegetables 
are  largely  produced  by 
fungi  or  bacteria. 

196.  Some  parasites 
spring  from  the  ground 
(Figs.  131,  132),  as 
other  plants  do,  but 
they  are  parasitic  on 
the  roots  of  their  hosts. 
Some  parasites  may  be 
partially  parasitic  and  partially  saprophytic.  Many  (perhaps 
most)  of  these  root-saprophytes  are  aided  in  securing  their 
food  by  soil  fungi,  which  spread  their  delicate  threads  over 
the  root-like  branches  of  the  plant  and  act  as  intermediaries 


135.   Saprophytic  fungus.    One  of  the  shelf  fungi 
(Polyporus)  growing  on  dead  trunks  and  logs. 


PARASITES   AND   SAPROPHYTES  93 

between  the  food  and  the  saprophyte.    The  roots  of  the 
coral-root    (Fig.    132)    are   covered   with   this   fungus,   and 
the   roots   have   practically   lost   the   power   of   absorbing 
nutrients  direct.    These  fungus-covered  roots  are  known  as 
mycorhizas    (meaning    "fungus     root").      Mycorhizas    are 
©    ^p^      not  peculiar  to  saprophytes.   They  are  found 
*e&  °©e>$i       on  many  wholly  independent  plants  as,  for 
c>^       e?%0        example,    the     heaths,     oaks,     apples    and 
*f»      pines.     It    is     probable    that     the    fungus- 
136.  Bacteria,  much    threads  perform  some  of  the  offices  of  rOOt- 
magnified.  hairg    ^    the   ^        Qn    the    other    hand>    the 

fungus    obtains    some    nourishment    from   the   host.     The 
association  seems  to  be  mutual. 

197.  Some  parasites  are  green-leaved.  Such  is  the  mistle- 
toe. They  anchor  themselves  on  the  host  and  absorb  its 
juices,  but  they  also  appropriate  and  use 
the  carbon  dioxid  of  the  air.  In  some 
groups  of  bacteria  the  process  of  photo- 
synthesis, or  something  equivalent  to  it, 
takes  place. 

198.  Parasitism  and  saprophytism  are 
usually  regarded  as  degeneration,  that  is, 
as  a  loss  of  independence.  The  ancestors 
of  these  plants  might  have  been  inde- 
pendent. Thus,  the  whole  class  of  fungi 
is  looked  upon  as  a  degenerate  evolution. 
The  more  a  plant  depends  on  other 
plants,  the  more  it  tends  still  further  to 

1  .,      •     j  j  137.  A   parasitic   fungus, 

lOSe  ltS  independence.  magnified.     The    my- 

199.  Epiphytes. — To  be  distinguished  part!'"*  sh<wraby the 
from  the  dependent  plants  are  those  that  ramiryingin  theP?e  a! 
grow  on  other  plants  without  taking  food  haustoria  projecting 
from  them.  These  are  green-leaved  plants  shown.06  Ther  Jong 
whose  roots  burrow  in  the  bark  of  the  fungu°fhang  f rom  the 
host  plant  and  perhaps  derive  some  food  UJaf.61  ? 


94  DEPENDENT    PLANTS 

from  it,  but  which  subsist  chiefly  on  materials  that  they 
secure  from  air-dust,  rain-water  and  the  air.  These  plants 
are  epiphytes  (meaning  "upon  plants")  or  air-plants. 

200.  Epiphytes  abound  in  the  tropics.  Orchids  are 
amongst  the  best  known  examples.  (Fig.  13.)  The  Spanish 
moss  or  tillandsia  of  the  South  is  another.  Mosses  and 
lichens  that  grow  on  trees  and  fences  may  also  be  called 
epiphytes.  In  the  struggle  for  existence,  the  plants  probably 
have  been  driven  to  these  special  places  in  which  to  find 
opportunity  to  grow.  Plants  grow  where  they  must,  not 
where  they  will. 

Review. — What  is  an  independent  plant?  Dependent?  Give 
examples.  How  are  dependent  plants  distinguished  from  others  in 
looks?  Define  saprophyte.  Parasite.  Give  examples.  What  is  a 
host?  How  does  a  parasitic  fungus  live  on  its  host?  What  is  meant  by 
plant  disease?  What  are  hyphse?  What  is  mycelium?  What  are  root- 
parasites?  Give  examples.  What  is  a  mycorhiza?  What  is  the  relation 
of  the  soil  fungus  to  its  host?  What  is  the  role  or  office  of  saprophytes 
in  nature?  Are  parasites  ever  green?  Explain.  What  has  probably 
been  the  evolution  of  most  parasites  and  saprophytes?  What  is  an 
epiphyte?  Give  examples.  How  do  epiphytes  live?  Why  may  they 
have  become  epiphytes? 

Note. — Usually,  the  most  available  parasite  is  the  dodder.  It  is 
common  in  swales  from  July  until  autumn,  winding  its  coral-yellow 
stems  about  herbs  and  soft-growing  bushes.  It  is  a  degraded  mem- 
ber of  the  morning-glory  family.  It  produces  true  flowers  and  seeds. 
These  seeds  germinate  the  following  spring.  The  slender  young  vine 
grows  from  the  ground  for  a  time,  but  if  it  fails  to  find  a  host,  it  perishes. 
One  of  the  dodders  is  a  pest  in  alfalfa  fields.  From  the  Ohio  River 
southward,  the  mistletoe  is  available. 


CHAPTER  XVI 

LEAVES   AND   FOLIAGE 

201.  Leaves  may  be  studied  from  two  points  of  view 
— with  reference  to  their  function,  or  what  they  do;  and 
with  reference  to  their  form,  or  their  shapes  and  kinds. 

202.  Function. — Leaves,  as  we  have  seen,  make  organic 
matter  from  carbon  dioxid.  Almost  any  part  of  the  plant, 
however,  may  bear  chlorophyll  and  perform  the  function 
of  leaves.  The  general  form  and  structure  of  leaves  is 
intimately  associated  with  their  function:  they  are  thin  and 
much  expanded  bodies,  thereby  exposing  the  greatest  pos- 
sible surface  to  light  and  air.  The  position  of  the  leaves 
usually  has  relation  to  light,  as  we  have  seen  (Chapter 
VIII).  Leaves  usually  hang  in  such  a  way  that  one  casts 
the  least  shade  on  the  other;  those  that  have  the  least 
favorable  positions  die  and  fall. 

203.  Parts. — Leaves  are  simple  or  un- 
branched  (Fig.  138),  and  compound  or 
branched  (Fig.  139).  The  method  of 
compounding  or  branching  follows  the 
style  of  veining.  The  veining,  or  venation, 
is  of  two  general  kinds:  in  most  plants 
the  main  veins  diverge,  and  there  is  a 
conspicuous  network  of  smaller  veins: 
such  leaves  are  netted-veined.  In  other 
plants  the  main  veins  are  parallel,  or 
nearly  so,  and  there  is  no  conspicuous 
network:  these  are  parallel-veined  leaves 
simple  loaf.  One  (Fig.  150).  The  venation  of  netted- 
veined  leaves  is  pinnate  or  feather-like, 
(95) 


of  the    cupatoriums    or 
bonesets. 


96 


LEAVES     AND     FOLIAGE 


when  the  veins  arise  from  the  side  of  a  continuous  midrib 
(Fig.  138);  palmate  or  digitate  (hand-like),  when  the  veins 

arise  from  the  apex  of 
the  petiole  (Fig.  140). 
If  the  leaf  were  divided 
between  the  main  veins, 
it  would  be  pinnately 
or  digitately  compound. 
204.  It  is  customary 
to  speak  of  a  leaf  as 
compound  only  when 
the  parts  or  branches 
are  completely  separate 
blades,  as  when  the 
139,141,142).  The  parts 
Sometimes  the  leaflets 
the 


139.  Compound  or  branched  leaf  of  brake 
(which  is  a  fern). 


division  extends  to  the  midrib  (Figs 
or  branches  are  known  as  leaflets 
themselves    are    compound,  and 
whole  leaf  is  then  said  to  be  bi-com- 
pound  or  twice-compound  (Fig.  139). 
Some  leaves  are  three-compound,  four- 
compound,  or  five-compound.  Decom- 
pound is  a  general  term  to  express  any 
degree  of  compounding  beyond  twice- 
compound. 

205.  Leaves  that  are  not  divided 
to  the  midrib  are  said  to  be: 

lobed,    openings 


140.   Digitate-veined  peltate 
leaf  of  nasturtium. 


141.  Pinnately  compound  leaf  of  ash. 


or    sinuses    not 

more  than  half  the  depth  of 

the  blade  (Fig.  143). 
cleft,    sinuses    deeper    than    the 

middle. 
parted,    sinuses    two -thirds     or 

more  to  the  midrib  (Fig.  144). 
divided,  sinuses  nearly  or   quite 

to  the  midrib. 


KTNDS    OF    LEAVES 


97 


142.  Digitately  com- 
pound leaf  of  rasp- 
berry. 

common    in 


The  parts  are  called  lobes,  divisions,  or  segments,  rather 

than  leaflets.   The  leaf  may  be  pinnately  or  digitately  lobed, 

parted,  cleft,  or  divided.    A  pinnately  parted 

or  cleft  leaf  is  sometimes  said  to  be  pinnatifid. 
206.  Leaves   may   have    one    or    all    of 

three  parts — blade  or  expanded  part,  petiole 

or  stalk,  stipules  or  appendages  at  the  base 

of  the  petiole.    All  these  parts  are  shown  in 

Fig.  145.    A  leaf  that  has  all  three  of  these 

parts  is  said  to  be  complete.  The  stipules 
are  often  green  and 
leaf-like  and  per- 
form the  function 
of  foliage,  as  in  the 
pea  and  Japanese 
quince  (the  latter 
yards). 

207.  Leaves  and  leaflets  that 
have  no  stalks  are  said  to  be  sessile 
(Fig.  149),  i.e.,  sitting.  The  same  is 
said  of  flowers  and  fruits.  The  blade 

of  a  sessile  leaf  may  partly  or  wholly  surround  the  stem, 

when  it  is  said  to  be  clasping  (Fig.  146).    In  some  cases  the 

leaf   runs  down  the  stem, 

forming  a  wing:  such  leaves 

are    said    to    be    decurrent 

(Fig.  147).    When  opposite 

sessile  leaves  are  joined  by 

their  bases,  they  are  said 

to  be  connate  (Fig.  148). 
208.  Leaflets  may  have 

one   or   all   of   those  three 

parts,  but  the  stalks  of  leaf- 
lets arc  called  pefriolvles  and 

the  stipules  of  leaflets  are 


143.  Lobed  leaf  of  sugar  maple. 


98 


LEAVES    AND     FOLIAGE 


called  stipels.    The  leaf  of  the  garden   bean   has  leaflets, 
petiolules,  and  stiples. 

209.  The  blade  is  usually  attached  to  the 
petiole  by  its  lower  edge.    In  pinnate-veined 
leaves,  the  petiole  seems  to  continue  through 
the  leaf  as  a  midrib   (Fig.    138).     In   some 
plants,   however,    the    petiole 
joins  the  blade  inside  or  be- 
yond the  margin   (Fig.   140). 
Such    leaves   are  said   to    be 
peltate  or  shield-shaped.     This 
mode  of   attachment   is   par- 
ticularly common  in  floating 
leaves  (e.g.,  the   water-lilies), 
us.  Compile  leaves   146.  Clasping  Fe'af   Peltate    1  e  a  v  e  s    are    usually 
of  willow.  of  wild  aster.      ciigitate-veined. 

210.  Shape. — Leaves  and  leaflets  are  infinitely  variable 
in  shape.  Names  have  been  given  to  some  of  the  more 
definite  or  regular  shapes.  These  names  are  a  part  of  the 
language  of  botany.  They  represent  ideal  or  typical  shapes, 
but  there  are  no  two  leaves  alike  and  very  few  that  perfectly 
conform  to  the  definitions.  The  shapes  are  likened  to  those 
of  familiar  objects  or  of  geometrical  figures: 
Linear,   several   times  longer   than   broad,   with  the  sides 

\     nearly  or  quite  parallel.     Spruces  and  most  grasses 
are  examples.    (Fig.  150.)    In  linear  leaves,  the  main 
veins  are  usually  parallel  to  the  midrib. 
Oblong,  twice  or  thrice  as  long  as  broad,  with  the  sides 

%    parallel  for  most  of  their  length.    Fig.  149  shows  the 
short-oblong  leaves  of  the  box,  a  plant  which  is  much 
used  for  edgings  in  gardens. 
Elliptic  differs  from  the  oblong  in  having  the  sides  gradu- 

Vally  tapering  to  either  end  from  the  middle.  The  Eu- 
ropean beech  (Fig.  151)  has  elliptic  leaves.  (This  tree 
is  often  planted.) 


SHAPES    OF    LEAVES  99 

Lanceolate,   four  to   six   times  longer  than   broad,   widest 

V   below  the  middle  and  tapering  to  each  end.    Some  of 
the    narrow-leaved    willows   are   examples.     Most   of 
the    willows    and   the  peach   have   oblong-lanceolate 
leaves. 
Spa tulate,  a  narrow  leaf  that  is  broadest  toward  the  apex. 

\The  top  is  usually  rounded.  It  is  much  like  an  oblong 
leaf. 
Ovate,  shaped  somewhat  like  the  longitudinal  section  of 
^  an  egg:  twice  as  long  as  broad,  tapering  from  near 
A  the  base  to  the  apex.  This  is  one  of  the  commonest 
^    leaf  forms.    (Fig.  152.) 

Obovate,  ovate  inverted, — the  wide  part  toward  the  apex. 
A  Leaflets  of  horse-chestnut  are  obovate.  This  form  is 
^,  commonest  in  leaflets  of  digitate  leaves. 
Reniform,  kidney-shaped.  This  form  is  sometimes  seen  in 
^^  wild  plants,  particularly  in  root-leaves.  Leaves  of 
"W   wild  ginger  are  nearly  reniform. 

Orbicular,  circular  in  general  outline.    Very  few  leaves  are 
^fe    perfectly  circular,  but  there  are  many  kinds  that  are 
^^    nearer  circular  than  any  other 
shape.    (Fig.  153.) 

The  shape  of  many  leaves  is 
described  in  combinations  of  these 
terms,  as  ovate-lanceolate,  lanceo- 
late-oblong. 

211.  The  shape  of  the  base  and  . 
apex  of  the  leaf  or  leaflet  is  often 

characteristic.     The   base   may  be  III  Decurrent 

rounded   (Fig.   138),  tapering    (Fig.  \||  mtdiein. 

127),  cordate  or  heart-shaped  (Fig. 
152),  truncate  or  squared  as  if  cut 
off.     The   apex   may   be   blunt  or  obtuse,  acute   or   sharp, 
acuminate  or  long-pointed,  truncate  (Fig.  154). 

212.  The  shape  of  the  margin  is  also  characteristic  of 


100 


LEAVES    AND     FOLIAGE 


148.  Two  pairs  of  connate  leaves 
of  honeysuckle. 


m 

% 


each  kind  of  leaf.  The  margin  is  entire  when  it  is  not  indented 
or  cut  in  any  way  (Fig.  149).  When  not  entire,  it  may  be 
undulate  or  wavy  (Fig.  140),  ser- 
rate or  saw-toothed  (Fig.  152), 
dentate  or  more  coarsely  notched 
(Fig.  138),  crenate  or 
round-toothed,  lobed, 
and  other  forms. 

213.  Leaves  often 
differ  greatly  in  shape 
on  the  same  plant. 
Observe  the  different 
shapes  of  leaves  on  the 
young  growths  of  mul- 
berries (Fig.  88)  and 
wild  grapes;  also  on  vigorous  squash  and  pumpkin 
vines.  In  some  cases  there  may  be  simple  and  com- 
pound leaves  on  the  same  plant.  This  is  marked 
in  the  so-called  Boston  ivy  or  ampelopsis  (Fig.  155), 
a  vine  which  is  used  to 
cover  brick  and  stone  build- 
ings. Different  degrees  of 
compounding,  even  in  the 
same  leaf,  may  often  be 
found  in  honey-locust  and 
Kentucky  coffee  tree.  Re- 
markable differences  in 
forms  are  seen  by  com- 
paring seed-leaves  with  mature  leaves 
of  any  plant  (Fig.  156). 

214.  The  Leaf  and  Its  Environ- 
ment.— The  form  and  shape  of  the 
leaf  often  have  direct  relation  to  the  place  in  which  the 
leaf  grows.  Floating  leaves  are  usually  expanded  and  flat, 
and  the  petiole  varies  in  length  with  the  depth  of  the  water. 


(& 


f7) 


€ 


7 


J 


V 


150.  Linear- 
acuminate 
leaf  of 
grass. 


[g:3 


149. 

Short-oblong  leaves  of  box. 


CHARACTERISTICS     OF     LEAVES 


101 


Submerged  leaves  are  usually  linear  or  thread-like,  or  are 
cut  into  very  narrow  divisions.-  Thereby  is  more  surface  ex- 
posed, and  possibly  the  leaves  are  less  injured  by  moving 
water. 


€ 


151.  Elliptic  leaf 
of  purple  beech. 


—J 

152.  Ovate  serrate  leaf 
of  hibiscus. 


215.  The  largest  leaves  on  a  sun-loving  plant  are  usually 
those  that  are  fully  exposed  to  light.  Compare  the  sizes  of 
the  leaves  on  the  ends  of  branches  with  those  at  the  base  of 
the  branches  or  in  the  interior  of  the  tree-top  (106).  In 
dense  foliage  masses,  the  petioles  of  the  lowermost  or  under- 
most leaves  tend  to  elongate — to  push 
the  leaf  to  the  light.    (Fig.  157.) 

216.  On  the  approach  of  winter  the 
leaf  ceases  to  work,  and  often  dies. 
It  may  drop,  when  it  is  said  to  be  de- 
ciduous;  or  it  may  remain  on  the  plant, 
when  it  is  said  to  be  persistent.  If 
persistent  leaves  remain  green  during 
the  winter,  the  plant  is  said  to  be 
evergreen.  Most  leaves  fall  by  break- 
ing off  at  the  lower  end  of  the  petiole 
with  a  distinct  joint  or  articulation. 
There  are  many  leaves,  however,  that  wither  and  hang 
on  the  plant  until  torn  off  by  the  wind:   of  such  are  the 


154.  Truncate  leaf  of 
tulip-tree. 


102 


LEAVES     AND     FOLIAGE 


155.  Different  forms  of  leaves  from 
one  plant  of  ampelopsis. 


leaves  of  grasses,  sedges,  lilies,  orchids,  and  other  plants 
known  as  monocotyledons  (Chapter  XXV).     Most  leaves 

of  this  character  are  paral- 
lel-veined. 

217.  Leaves  also  die  and 
fall  from  lack  of  light.  Ob- 
serve the  yellow  and  weak 
leaves  in  a  dense  tree-top 
or  in  any  thicket.  Why  do 
the  lower  leaves  die  on 
house-plants?  Note  the 
carpet  of  needles  under  the 
pines.  All  evergreens  shed 
their  leaves  after  a  time. 
Counting  back  from  the  tip 
of  a  pine  or  spruce  shoot, 
determine  how  many  years 
the  leaves  persist.  (Fig.  158.)  In  some  spruces  a  few  leaves 
may  be  found  on  branches  ten  or  more  years  old. 

218.  Although  the  forms  and  positions  of  leaves  often 
have  direct  relation  to  the  places  and  conditions  in  which 
the  leaves  grow,  it  is  not  probable  that  all  forms  and  shapes 
have  been  developed  to  adapt  the  plant  to  its  environment. 
It  is  probable  that  the  toothing  or  lobing  of  the  leaf-margins 
is  due  to  the  same  causes  that  produce  compounding  or 
branching  of  leaves,  but 
what  these  causes  are  is 
not  known.  It  has  been 
suggested  that  leaves  have 
become  compound  in  order 
to  increase  their  surface  and 
thereby  to  offer  a  greater 
exposure  to  light  in  shady  places,  but  very  many  sun-loving 
species  have  compound  leaves,  and  many  shade-loving 
species  have  simple  and  even  small  leaves.    Again,  it  has 


156.   Muskmelon  seedlings,  with  the  unlike 
seed-leaves  and  true 


CHARACTERISTICS   OF   LEAVES 


103 


been    suggested   that   compound   leaves   shade   underlying 
leaves  less  than  simple  leaves  do. 

219.  How  to  Tell  a  Leaf. — It  is  often  difficult  to  dis- 
tinguish compound  leaves  from  leafy  branches,  and  leaflets 


157.  A  leaf  mosaic  of  Norway  maple.    Note  the  varying  lengths  of  petioles. 

from  leaves.  As  a  rule,  leaves  can  be  told  by  the  follow- 
ing tests:  (1)  Leaves  are  temporary  structures,  sooner 
or  later  falling.  (2)  Usually  buds  are  borne  in  their  axils. 
(3)  Leaves  are  usually  borne  at  joints  or  nodes.  (4)  They 
arise  on  wood  of  the  current-year's  growth.  (5)  They  have 
a  more  or  less  definite  arrangement.  When  leaves  fall,  the 
twig  that  bore  them  remains;  when  leaflets  fall,  the  main 
petiole  that  bore  them  falls  also. 

Review. — How  may  leaves  be  studied?  What  is  meant  by  function? 

What   do   leaves  do?     What    other   parts   may   perform   the   function 


104 


LEAVES    AND     FOLIAGE 


of  leaves?  How  is  the  form  of  leaves  associated  with  their  function? 
What  are  simple  leaves?  Compound?  What  is  venation?  What  are 
the  types  or  kinds  of  venation?  What  are  the  two  types  of  compound 
leaves?  What  is  a  leaflet?  Define  bi-compound;  decompound. 
What  are  lobed,  cleft,  parted,  and  divided  leaves?  Pinnatifid 
leaf?  Complete  leaf?  Complete  leaflet?  What  is  a  sessile  leaf? 
How  may  the  petiole  join  the  blade?  How  are  the  shapes  of  leaves 
named  or  classified?  Define  the  shapes  described  in  210.  Describe 
common  shapes  of  the  base  of  the  leaf.  Of  the  apex.  Of  the  margin. 
How  are  the  forms  and  sizes  of  leaves  ever  related  to  the  place  in  which 
they  grow?  Why  do  leaves  fall?  Define  deciduous.  Persistent.  Ever- 
green.   When  do  pine  leaves  fall?    How  can  you  distinguish  leaves? 


158.   Shoot  of  the  common  white  pine,  one-third  natural  size. 
The  picture  shows  the  falling  of  the  leaves  from  the  different  years'  growth.    The 
part  of  the  branch  between  the  tip  and  A  is  the  last  season's  growth;  between  A  and 
B  it  is  two  years  old;  the  part  between  B  and  C  is  three  years  old;  it  has  few  leaves. 
The  part  that  grew  four  seasons  ago — beyond  C — has  no  leaves. 


CHAPTER   XVII 

MORPHOLOGY,   OR  THE   STUDY   OF   THE   FORMS   OF 
PLANT   MEMBERS 

220.  Botanists  interpret  all  parts  of  the  plant  in  terms 
of  root,  stem  and  leaf.  That  is,  the  various  parts,  as  thorns, 
flowers,  fruits,  bud-scales,  tendrils,  and  abnormal  or  un- 
usual members,  are  supposed  to  represent  or  to  stand  in 
the  place  of  roots,  stems  (branches)  or  leaves. 

221.  The  forms  of  the  parts  of  plants  are  interesting, 
therefore,  in  three  ways:  (1)  merely  as  forms,  which  may 
be  named  and  described;  (2)  their  relation  to  function,  or 
how  they  enable  the  part  better  to  live  and  work;  (3)  their 
origin,  as  to  how  they  came  to  be  and  whether  they  have 
been  produced  by  the  transformation  or  modification  of 
other  parts.  The  whole  study  of  forms  is  known  as  morphology 
(literally,  the  "science  of  forms")-  We  may  consider  examples 
in  the  study  of  morphology. 

222.  It  is  customary  to  say  that  the  various  parts  of 
plants  are  transformed  or  modified  root,  stem  or  leaf,  but 
the  words  transformation  and  modification  are  not  used  in 
the  literal  sense.  It  is  meant  that  the  given  part,  as  a  tendril, 
may  occupy  the  place  of  or  represent  a  leaf.  It  was  not 
first  a  leaf  and  then  a  tendril:  the  part  develops  into  a  ten- 
dril instead  of  into  a  leaf:  it  stands  where  a  leaf  normally 
might  have  stood:   it  is  the  historical  descendant  of  the  leaf. 

223.  It  is  better  to  say  that  parts  which  have  similar 
origins,  which  arise  from  the  same  fundamental  type,  or 
which  are  of  close  genealogical  relationship,  are  homol- 
ogous. Thus  the  tendril,  in  the  example  assumed  above, 
is  homologous  with  a  leaf.     Parts  that  have  similar  func- 

(105) 


106 


MORPHOLOGY 


tions  or  perform  similar  labor,  without  respect  to  origins, 
are  analogous.  Thus  a  leaf-tendril  is  analogous  to  a  branch- 
tendril,  but  the  two  are  not  homologous. 

224.  There  are  five  tests  by  means  of  which 
we  may  hope  to  determine  what  a  given  part 
is:  (1)  by  the  appearance  or  looks  of  the  part 
(the  least  reliable  test) ;  (2)  by  the 
position  of  the  part  with  relation 
to  other  parts — its  place  on  the 
plant;  (3)  by  comparison  with 
similar  parts  on  other  plants 
(comparative  morphology);  (4)  by 
study  of  intermediate  or  connecting 
parts;  (5)  by  study  of  the  develop- 
ment of  the  part  in  the  bud  or  as  it  originates  by  means  of 
the  microscope  (embryology).  The  last  test  can  be  applied 
only  by  the  trained  investigator,  but  it  often  gives  the  most 
conclusive  evidence.  Even  with  the  application  of  all  these 
tests,  it  is  sometimes  impossible  to  arrive  at  a  definite  con- 


159.  Leaf  and 
cladophyllaof 
asparagus. 


160.   Leaves  of 
asparagus. 


161.  Fern-like  leaf-branches  of  a 
greenhouse  asparagus. 


elusion  as  to  the  origin  or  morphology  of  a  part.  For  ex- 
ample, it  is  not  yet  agreed  whether  most  cactus  spines 
represent  leaves  or  branches,  or  are  mere  outgrowths  of  the 
epidermis  (as  hairs  are). 


LEAF-BRANCHES 


107 


225.  The  foliage 
of  asparagus  is  com- 
posed of  modified 
branches.  The  true 
leaves  of  asparagus 
are  minute  whitish 
scales,  (a,  Fig.  159.) 
The  green  foliage  is 
produced  in  the  axils 
of  these  scales.  On 
the  strong  spring 
shoots  of  asparagus, 
which  are  edible,  the 
true  leaves  appear  as 
large  scales,  (a,  a, 
Fig.  160.)  These 
large  scales  persist  on  the  base  of 
the  asparagus  plant,  even  in  the 

fall.    In  the  species  of  greenhouse  or  ornamental 

asparagus,  the  delicate  foliage  is  also  made  up  of 

green  leaf-like  branches.    (Fig.  161.)    In  some  cases 

the  true  leaves  fall  after  a  time,  and  there  is  little 

evidence  left.    The  strong  new  shoots  usually  show 

the  true  leaves  plainly  (as  in  Fig.  162).    Branches 

that  simulate  leaves  are  known  as  cladophylla 

(singular,  cladophyllum).   The  broad  flat  leaves 

of  florists'  smilax  (common  in  glasshouses)  are 

cladophylla. 

226.  In  the  study  of  morphology,  it  is  not 
enough,  however,  merely  to  determine 
whether  a  part  represents  root,  stem  or 
leaf:  one  must  determine  what  part  or 
kind  of  root,  stem  or  leaf  it  stands  for. 
For  example,  the  foliage  in  Fig.  163  rep- 
resents green  expanded  petioles.     These 


163.  Phyllodia  of  aca- 
cia. These  Australian 
trees  are  sometimes 
grown  in  glasshouses. 


108 


MORPHOLOGY 


1G4.  The  thorns  are  in  the  axils 
of  leaves. 


leaf-like  members  have  buds  (which  produce  branches)  in  their 
axils,  and  they  have  the  arrangement  or  phyllotaxy  of  leaves ; 
therefore  they  are  considered  to  be 
true  leaf  parts.  But  they  stand 
edgewise  as  if  they  might  be  pet- 
ioles; sometimes  they  bear  leaf- 
blades;  other  acacias  have  com- 
pound expanded  leaves;  there  are 
intermediate  forms  or  gradations 
between  different  acacias;  young 
seedlings  sometimes  show  intermediate 
forms.  From  all  the  evidence,  it  is  now 
understood  that  the  foliage  of  the  simple- 
leaf  acacias  represents  leaf-like  petioles. 
Such  petioles  are  known  as  phyllodia  (sin- 
gular, phyllodium). 

227.  Thorns  and  strong  spines  are  usu- 
ally branches.  The  spines  of  hawthorns 
or  thorn-apples  are  examples:  they  are 
borne   in   the  axils 

of  leaves  as  branches  are  (Fig.  164); 
hawthorns  usually  bear  two  or  more 
buds  in  each  axil  (Fig.  165),  and  one 
or  two  of  these  buds  often  grow  the 
following  year  into  normal  leafy 
branches  (Fig.  166) ;  sometimes  the 
thorn  itself  bears  leaves.  (Fig.  167.) 
The  thorns  of  wilding 
pears,  apples  and  plums 
are  short,  hardened  branches.  In  well-culti- 
vated trees  there  is  sufficient  vigor  to  push  the 
main  branch  into  longer  and  softer  growth,  so 
that  the  side  buds  do  not  have  a  chance  to 
start.  The  thorns  of  osage-orange  and  honey- 
locust  are  also  branches.    Those  of  the  honey-    may  bear  leave". 


165.  Two  or  more  buds 
are  borne  in  the  axils. 


166.   Some  of  the  buds  pro 
duce  leafy  branches. 


PRICKLES    AND    SPINES 


109 


locust    usually  arise    from    supernumerary 
borne  somewhat  above  the  axils. 

228.  Prickles,  bristles  and  weak  spines 
definite  arrangement  on  the  stem,  are  usually 
modified  leaves  or  parts  of  leaves.  The  spines 
of  thistles  are  hardened  points  of  leaf-lobes. 
The  spines  of  the  barberry  are  reduced 
leaves;  in  their  axils  are  borne  short  branches 


buds    that 


which   have   a 


1 


168.   Leaf-spine  ot 
barberry. 


or  leaf-tufts  (Fig.  168);  in 
spring  on  young  shoots  may 
be  found  almost  complete  gradations  from 
spiny  leaves  to  spines.  The  prickly  ash  has 
prickles  (Fig.  169)  that  simulate  stipules 
and  stipels,  but  the  irregularity  of  position 
indicates  that  they  are  not  homologous  with 
stipules.  The  prickles  of  the  common  locust 
(robinia)  are  usually  interpreted  as  stipules. 
229.  Prickles,  bristles  and  hairs  that  are 
scattered  or  have  no  definite  arrangement,  are 
usually  mere  outgrowths  of  the  epidermis. 
They  commonly  are  removed  with  the  bark. 
Of  such  are  the  prickles  of  squashes,  briars 
(Fig.  170),  and  the 


169.  Small  prickles  of 
the  prickly  ash. 


roses. 

230.  The  reason 
for  the  existence  of  spines  is  difficult 
to  determine.  In  many  or  most 
cases  they  seem  to  have  no  distinct 
use  or  function.  In  some  way  they 
are  associated  with  the  evolution  of 
the  plant,  and  one  cannot  deter- 
mine why  they  came  without  know- 
ing much  of  the  genealogy  of  the 
plant.  In  some  cases  they  seem  to 
contraction  of  the  plant-body,   as  in 


170.  Prickles  of  dewberry. 

be  the  result  of  the 
the  cacti  and  other 


110 


MORPHOLOGY 


171.  The  diminishing  leaves 
of  boneset. 


desert  plants;  and  they  may  then  serve  a  purpose  in  lessen- 
ing transpiration.  It  is  a  common  notion  that  spines  and 
prickles  exist  for  the  purpose  of  keep- 
ing enemies  away,  and  that  hairs  keep 
the  plant  warm,  but  these  ideas  usu- 
ally lack  scientific  accuracy.  Even  if 
spines  do  keep  away  browsing  animals 
in  any  plant,  it  is  quite  another  ques- 
tion why  the  spines  came  to  be.  To 
determine  what  spines  and  hairs  are 
for  demands  close  scientific  study  of 
each  particular  case,  as  does  any  other 
problem. 

231.  Leaves  are  usually  smaller  as 
they  approach  the  flowers.  (Fig.  171.) 
They  often  become  so  much  reduced 
as  to  be  mere  scales,  losing  their  office  as  foliage.  In  their 
axils,  however,  the  flower-branches  may  be  borne.  (Fig.  172.) 
Much-reduced  leaves,  particu- 
larly those  that  are  no  longer 
green  and  working  members, 
are  called  bracts.  In  some 
cases,  large  colored  bracts  are 
borne  just  beneath  the  flowers 
and  look  like  petals:  the  flow- 
ering dogwood  is  an  example; 
also  the  bougainvillea,  which  is 
common  in  glasshouses ;  also  the 
scarlet  sage  of  gardens,  some  of 
the  euphorbias  or  spurges,  and 
the  flaming  poinsettia  of  green- 
houses. Sometimes  a  green  leaf 
is  borne  close  against  a  head  or 
cluster  of  flowers,  as  in  the  clover  (Fig.  173);  but  a  separate 
bract  or  scale  will  be  found  for  each  flower  in  the  head. 


172.  The  uppermost  flowers  are  borne 
in  the  axils  of  bracts. — Fuchsia. 


BUD-SCALES 


111 


232.  The  scales  of  buds  are  special  kinds  of  bracts.  In 
some  cases  each  scale  represents  an  entire  leaf;  in  others, 
it  represents  a  petiole  or  stipule. 
In  the  expanding  pear,  maple,  lilac, 
hickory  and  horse-chestnut  buds, 
note  the  gradation  from  dry  scales  to  ^, 
green  leaf-like  bodies.  When  the 
winter  scales  fall  by  the  pushing  out 
of  the  young  shoot,  scars  are  left: 
these  scars  form  "rings,"  which  mark 
the  annual  growths.  (See  Chap.  VII.) 
The  scales  of  bulbs  are  also  special 
kinds  of  leaves  or  bracts.  In  some 
cases  they  are  merely  protective  bodies) 
in  others  they  are  storehouses.  We 
have  found  (45)  that  the  presence  of 
scales  or  bracts  is  one  means  of  dis- 
tinguishing underground  stems  from 

173.  Red  clover.    Leaves 
rOOtS.  3-foliolate. 


Review. — What  are  considered  to  be  the  fundamental  or  type 
forms  from  which  the  parts  of  plants  are  derived?  How  do  the  forms 
of  plants  interest  us?  What  is  morphology?  What  is  meant  by  trans- 
formation and  modification  as  used  by  the  morphologist?  What  is 
meant  by  homologous  parts?  Analogous  parts?  Tell  how  one  may 
determine  the  morphology  of  any  part.  What  is  a  cladophvllum? 
Phyllodium?  Show  a  specimen  of  one  or  the  other,  or  both  (canned 
asparagus  can  always  be  had  in  the  market).  What  is  the  morphology 
of  most  thorns?  Explain  the  thorns  of  hawthorn.  What  are  bristles, 
prickles  and  hairs?  Why  do  spines  and  bristles  exist?  Explain  what 
a  bract  is.    A  bud-scale.    A  bulb-scale. 


CHAPTER  XVIII 

HOW   PLANTS    CLIMB 

233.  We  have  seen  that  plants  struggle  or  contend  for 
a  place  in  which  to  live.  Some  of  them  have  become  suited  to 
grow  in  the  forest  shade,  others  to  grow  on  other  plants  as 
epiphytes,  others  to  climb  to  the  light.  Observe  how  woods 
grapes,  and  other  forest  climbers,  spread  their  foliage  on 
the  very  top  of  the  forest  tree,  while  their  long  flexile  trunks 
may  be  bare.  One  who  has  seen  a  dense  tropical  forest  has 
realized  the  struggle  for  light  on  the  tops  of  the  trees. 

234.  There  are  several  ways  by  which  plants  climb,  but 
most  climbers  may  be  classified  into  four  groups:  (1)  scram- 
blers, (2)  root-climbers,  (3)  tendril-climbers,  (4)  twiners. 

■  235.  Scramblers.— Some  plants  rise  to  light  and  air  by 
resting  their  long  and  weak  stems  on  the  tops  of  bushes 
and  quick-growing  herbs.    Their  stems  are  elevated  by  the 

growing  twigs  of  the  plants 

_Jtl — jteffifr—  on  which  they  recline.  Such 

plants  are  scramblers.  Usu- 
ally they  are  provided  with 
prickles  or  bristles.  In  most 
weedy  swamp  thickets, 
scrambling  plants  may  be 
found.  Briars,  some  roses, 
bed-straw  or  galium,  bitter- 
sweet (Solanum  Dulcamara, 
not  the  celastrus),  the  tear- 
thumb  polygonums,  and  other  plants  are  familiar  examples 
of  scramblers. 

236.  Root-climbers. — Some   plants   climb   by   means   of 
(112) 


174.  A  root-climber. — The  English  ivy. 


CLIMBERS  113 

true  roots,  as  explained  in  paragraph  31.  These  roots 
are  of  adventitious  origin.  They  grow  in  a  horizontal  di- 
rection and  enter  the  chinks  of  walls  or  the  furrows  in  the 
bark  of  trees.  Fig.  12,  the  trumpet  creeper,  is  a  familiar 
example.  The  true  or  English  ivy,  which  is  often  grown  to 
cover  buildings,  is  another  example.  (Fig.  174.)  Still  another 


175.  Tendril  of  Virginia  creeper.    The  direction  of  the  coil  changes  near  the  middle 

is  the  poison  ivy.  Roots  are  distinguished  from  stem  tendrils 
by  their  irregular  or  indefinite  position  as  well  as  by  their 
mode  of  growth. 

237.  Tendril-climbers. — A  slender  coiling  part  that 
serves  to  hold  a  climbing  plant  to  a  support  is  known  as  a 
tendril.  The  free  end  swings  or  curves  until  it  strikes  some 
object,  when  it  attaches  itself  and  then  coils  and  draws  the 
plant  close  to  the  support.  The  spring  of  the  coil  also  allows 
the  plant  to  move  in  the  wind,  thereby  enabling  the  plant 
to  maintain  its  hold.  Slowly  pull  a  well-matured  tendril 
from  its  support,  and  note  how  strongly  it  holds  on.  Watch 
the  tendrils  in  a  storm.  To  test  the  movement  of  a  free  ten- 
dril, draw  an  ink  line  lengthwise  of  it,  and  note  that  the  line 
is  now  on  the  concave  side  and  now  on  the  convex  side. 
Of  course  this  movement  is  slow,  but  often  it  is  evident  in 
an  hour  or  so.  Usually  the  tendril  attaches  to  the  support 
by  coiling  about  it,  but  the  Virginia  creeper  and  Boston  ivy 
attach  to  walls  by  means  of  disks  on  the  ends  of  the  tendrils. 

H 


114  HOW    PLANTS    CLIMB 

238.  Since  both  ends  of  the  tendril  are  fixed,  when  it 
finds  a  support,  the  coiling  would  tend  to  twist  it  in  two.  It 
will  be  found,  however,  that  the  tendril  coils  in  different 
directions  in  different  parts  of  its  length.  In  Fig.  175  the 
change  of  direction  in  the  coil  occurs  at  the  straight  place 
beyond  the  middle.  In  long  tendrils  of  cucumbers  and 
melons  there  may  be  several  changes  of  direction. 


176.  The  fruit-cluster  and  tendril  of  grape  are  homologous. 

239.  Tendrils  may  be  either  branches  or  leaves.  In 
the  Virginia  creeper  and  grape  they  are  branches;  they 
stand  opposite  the  leaves  in  the  position  of  fruit-clusters 
(Fig.  176),  and  sometimes  one  branch  of  a  fruit-cluster 
is  a  tendril.  These  tendrils  are  therefore  homologous  with 
fruit-clusters,  and  fruit-clusters  are  branches. 

240.  In  some  plants  tendrils  are  leaflets.  Examples  are 
the  sweet  pea  (Fig.  177)  and  common  garden  pea.  In 
Fig.   177,  observe  the  leaf  with  its  two  stipules,  petiole, 


CLIMBERS 


115 


two  normal  leaflets  and  two  or  three  pairs  of  leaflet-tendrils 
and  a  terminal  leaflet-tendril.  The  cobea,  a  common  gar- 
den climber,  has  a  similar  arrangement.  In  some  cases 
tendrils  are  stipules,  as  probably  in  the  greenbriers  (smilax). 
241.  The  petiole  or  midrib  may  act  as  a  tendril,  as  in 
various  kinds  of  clematis.  In  Fig.  178,  two  opposite  leaves 
are  attached  at  a.    Each  leaf  is  pinnately  compound  and 


In  the  sweet  pea  (and  garden  pea)  the  leaflets  are  tendrils 


has  two  pairs  of  leaflets  and  a  terminal  leaflet.  At  b  and 
c  the  midrib  or  rachis  has  wound  about  a  support.  The 
petiole  and  the  petiolules  may  behave  similarly.  Examine 
the  tall-growing  nasturtiums  in  the  garden. 

242.  Twiners. — The  entire  plant  or  shoot  may  wind 
about  a  support.  Such  a  plant  is  a  twiner.  Examples 
are  bean,  hop,  morning-glory,  moon-flower,  false  bitter- 
sweet  or   wax- work    (celastrus),    some    honeysuckles,    wis- 


116 


HOW    PLANTS    CLIMB 


taria,  Dutchman's  pipe,  dodder.  The  free  tip  of  the  twining 
branch  sweeps  about  in  curves,  much  as  the  tendril  does, 
until  it  finds  support  or  becomes  old  and  rigid. 

243.  Each  kind  of  plant  usually  coils  in  only  one  direction. 
Most  plants  coil  against  the  sun,  or  from  the  observer's 


178.  Clematis  climbs  by  means  of  its  leaf-stalks. 

left  across  his  front  to  his  right  as  he  faces  the  plant. 
Such  plants  are  said  to  be  antitropic,  or  to  move  against 
the  sun  from  the  position  in  which  the  observer  stands. 
Examples  are  bean,  morning-glory.  The  hop  twines  from 
the  right  to  his  left;  such  plants  are  eutropic  (with  the  sun). 
Fig.  179  shows  the  two  directions. 


CLIMBERS 


117 


Review. — How  do 
plants  climb?  Explain 
what  is  meant  by 
scramblers.  By  root- 
climbers.  What  is  a 
tendril?  How  does  it 
find  a  support?  How 
does  it  coil?  How  does 
it  grasp  its  support? 
What  is  the  morphol- 
ogy of  the  tendril  of 
Virginia  creeper?  Of 
the  pea?  Of  the  clem- 
atis? What  is  a 
twiner?  How  does  it 
find  a  support?  What 
is  an  antitropic  twiner? 
Eutropic? 

Note. —  The  pupil 
may  not  un- 
derstand why 
the  branch  (as 
tendril  and 
flower-cluster) 
stands  o  p  p  o  -  c 

site  the  bud  in  the  grape  and  Virginia  creeper.     Not 

grape-shoot    ends    in   a   tendril    (a,    Fig.    180).      The 

represents  the  true  axis   of  the   shoot.    On  the  side 

borne,  from   the  axil  of  which   the  branch  grows  to 

the    shoot.      This    branch    ends    in    a    tendril,    b. 

Another  leaf   has   a  branch   in   its   axil,   and  this 

branch  ends  in  the  tendril  c.    The  real  apex  of  the 

shoot  is  successively  turned  aside  until  it  appears 

to  be  lateral.    That  is,  the  morphologically  terminal 

points  of  the  successive  shoots  are  the  tendrils,  and 

the  order  of  their  appearing  is  a,  b,  r.    The  tendrils 

branch:    observe  the   minute   scale    representing  a 

leaf  at  the  base  of  each  branch.   This  type  of  branch- 
ing— the  axial  growth  being  continued  by  successive 

lateral   buds — is   aympodial,    and   the   branch    is   a 

8ympode.    Continuous  growth  from  the  terminal  bud 

is  monopodial,  and  the  branch  is  a  monopode. 


2 


f 


e  that  a  vJ 

tendril  ^ 

a  leaf  is  >m 

continue  'n 


180.   Sympodo 
of  the  grupi'. 


CHAPTER  XIX 


FLOWER-BRANCHES 


^fe^ 


244.  We  have  seen   (87)   that  branches  arise  from  the 

axils  of  leaves.    Sometimes  the  leaves  may  be  reduced  to 

bracts  and  yet  branches  are  borne  in  their  axils  (225).   Some 

of  the  branches  grow  into  long  limbs;  others  become  short 

spurs  or  thorns  (227) ;  others  bear  flowers. 

£  245.  Flowers  are  usually  borne  near  the 

top  of  the  plant,  since  the  plant  must  grow 
before  it  blooms.  Often  they  are  produced  in 
great  numbers.  It  results,  therefore,  that 
flower-branches  usually  stand  close  together, 
forming  a  cluster.  The  shape  and  arrange- 
ment of  the  flower-cluster  differ  with  the  kind 
of  plant,  since  each 
plant  has  its  own  mode 
of  branching. 

246.  Certain  definite 
or  well  -  marked  types 
of  flower-clusters  have 
received  names.  Some 
of  these  names  we  shall 

but     the 
flower-clusters  that 

perfectly  match  the  definitions  are 

the  exception  rather  than  the  rule. 

The  determining  of  the  kinds  of 

flower-clusters  is  one  of  the  most 

perplexing  subjects  in  descriptive 

botany.   We  may  classify  the  sub- 
(118) 


181.   Solitary  ter- 
minal flower  of     disCUSS, 


182. 
Lateral  flower 
of  abutilon. 


CORYMBS 


119 


ject  around  three  ideas:  solitary 
flowers,  corymbose  clusters,  cymose 
clusters. 

247.  Solitary  Flowers.— In 
many  cases  flowers  are  borne 
singly.  They  are  then  said  to  be 
solitary.  The  solitary  flower  may 
be  either  at  the  end  of  the  main 
shoot  or  axis  (Fig.  181),  when  it 
is  said  to  be  terminal,  or  from 
the  side  of  the  shoot  (Fig.  182), 
when  it  is  said  to  be  lateral. 
The  lateral  flower  is  also  said  to  be  axillary. 

248.  Corymbose     Clusters. 


183.  Leafy  flower-cluster  of  fuchsia. 


184.   Racemes  of  sweet 
clover. 


If     the 

flower -bearing  axils  were  rather  close 
together,  an  open  or  leafy  flower-cluster 
might  result,  as  in  Fig.  183.  The  fuchsia 
continues  to  grow  from  the  tip,  and  the 
older  flowers  are  left  farther  and  farther 
behind.  If  the  cluster  were  so  short  as 
to  be  flat  or  convex  on  top,  the  outer- 
most flowers  would  be  the  older.  A 
flower-cluster  in  which  the  lower  or  outer 
flowers  open  first  is  said  to  be  a  corym- 
bose cluster.  It  is  sometimes  said  to  be 
an  indeterminate  cluster,  since  it  is  the  re- 
sult of  a  type  of  growth  which  may  go  on 
more  or  less  continuously  from  the  apex. 
249.  The  simplest  form  of  a  definite 
corymbose  cluster  is  a  raceme,  which  is 
an  unbranched  open  cluster  in  which  the 
flowers  are  borne  on  short  stems  and 
bloom  from  below  (that  is,  from  the  older 
part  of  the  shoot)  upwards.  The  raceme 
may  be  terminal  to  the  main  branch,  or  it 


120 


FLOWER-BRANCHES 


may  be  lateral  to  it,  as 
in  Fig.  184.  Racemes 
often  bear  the  flowers 
on  one  side  of  the  stem, 
or  in  a  single  row. 

250.  When  a  corym- 
bose flower -cluster  is 
long  and  dense  and  the 
flowers  are  sessile  or 
nearly  so,  it  is  called  a 
spike  (Figs.  185,  186). 
Common  examples  of 
spikes  are  plantain, 
mignonette,  mullein. 

251.  A  very  short 
and  dense  spike  is  a  head, 
187)  are  examples 


186.  Spike    of 


hyaci  n  th. 
Note,  also, 
that  the 
flowers  and 
foliage  are 
produced 
from  the 
stored  food 
in  the  bulb, 
only  water 
being  given. 


Clovers  (Figs.  173, 
The  sunflower  and  related 
plants  bear  many  small  flowers  in  a  very  dense 
head.  This  special  kind  of  head  of  the  sun- 
flower, thistle  and  aster  tribes  has  been  called 
an  anthodium,  but  this  word  is  little  used.    Note 

that  in  the  sunflower  (Fig.  188)  the  outside  or 
exterior  flowers  open  first.  Very  often  the  antho- 
dium terminates  the  main  stem,  as  m  Fig.  189. 

252.  Another 
special  form  of 
spike  is  the  cat- 
kin, which  usu- 
ally has  scaly 
bracts  and  the 
whole  cluster  is 
deciduous  after 
""  jM  If      flowering     or 

^^^^FT  fruiting,  and  the 

Ga  clover.mSO  188.  Head  of  sunflower.  flowers  (in  typi- 


CORYMBS 

cal  cases)  have  only  one  sex.  Ex- 
amples are  the  "pussies"  of  willows 
(Fig.  229)  and  flower-clusters  of 
oaks  (Fig.  228),  hickories,  poplars 
and  walnut  (Fig.  190). 

253.  When  a  loose,  elongated 
corymbose  flower-cluster  branches, 
or  is  compound,  it  is  called  a  pan- 
icle. Because  of  the  earlier  growth 
of  the  lower  branches,  the  panicle 
is  usually  broadest  at  the  base  or 
conical  in  outline.  The  flower- 
cluster  of  the  oat  is  an  example. 
(Fig.  191.)  True  panicles  are  not 
common. 

254.  When  an  indeterminate 
flower-cluster  is  short,  so  that  the 

top  is  con- 


121 


oCT)7 


r* 


189.  Terminal  heads  of  the  white- 
weed  (in  some  places  erro- 
neously called  ox-eye  daisy). 


190.  Catkins  of  black  walnut, 
at/).  Pistillate  flowers  at  a. 
Paragraph  284. 


vex  or  flat, 
it  is  a 
corymb. 
(Fig.  192.) 
The  outer- 
most flowers  open  first.  Fig.  193 
shows  many  corymbs  of  the  bridal 
wreath,  one  of  the  spireas. 

255.  When  the  branches  of  an 
indeterminate  cluster  arise  from  a 
common  point,  like  the  frame  of 
an  umbrella,  the  cluster  is  an  umbel. 
(Fig.  194.)  Typical  umbels  occur 
in  carrot,  parsnip,  parsley  and  other 
plants  of  the  parsley  family:  the 
family  is  known  as  the  Umbelliferae 
or    umbel -bearing    family.      In    1 1  * 


122 


FLOWER-BRANCHES 


carrot  and  many  other  Umbelliferse, 
there  are  small  or  secondary  umbels, 
called  umbellets,  at  the  end  of  each  of 
the  main  branches.  (In  the  center  of 
the  wild  carrot  umbel  one  often  finds  a 
single,  purplish,  often  aborted  flower, 
comprising  a  1-flowered  umbellet). 

256.  Cymose  Clusters. — When  the 
terminal  or  central  flower  opens  first, 
the  cluster  is  said  to  be  cymose.  The 
growth  of  the  shoot  or  cluster  is  deter- 
minate, since  the  length  is  definitely 
determined  or  stopped  by  the  terminal 
flower.  Fig.  195  shows  a  determinate 
or  cymose  mode  of  flower-bearing. 

257.  Dense  cymose  clusters  are 
usually  flatfish  on  top  because  of  the 

cessation  of  growth  in  the  main 
or  central   axis,  but  cymes  are 


•*&*■#.*. 


192.  Corymb  of  candytuft. 


of  the  bridal  wreath  (apirea). 


CYMES 


123 


194.  Compound  umbel  of 
wild  carrot. 


sometimes  open  and  loose. 
These  flower-clusters  are  known 
as  cymes.  Apples,  pears  (Fig. 
196)  and  cherries  bear  flowers 
in  cymes.  Some  cyme -forms 
are  like  umbels  in  general  ap- 
pearance. A  head-like  cymose 
cluster  is  a  glomerule:  it  blooms 

from  the  top  downwards  rather  than 
from  the  base  upwards. 

258.  Centripetal  and  Centrifugal. — 
A  cluster  in  which  the  outermost 
(or  lowermost)  flowers  open  first  is 
corymbose  or  indeterminate,  as  we 
have  learned;  it  is  also  said  to  be 
centripetal  (meaning  "toward  the  cen- 
ter"). A  cluster  in  which  the  inner- 
most or  central  flowers  open  first  is 
cymose  or  determinate;  it  is  also  said 
to  be  centrifugal  (meaning  "away  from 
the  center").  These  contrasts  can 
best  be  under- 
stood by  study 
of  diagrams, 
since  actual 
clusters  so  often 
vary  from  the 
assumed  stan- 
dard. Such  diagrams  are  presented  in 
Figs.  197,  198,  199. 

259.  Mixed    Clusters.— Often   the  19G-  Cyne of  pear 

cluster  is  mixed,  being  determinate  in  one  part  and  indeter- 
minate in  another  part  of  the  same  cluster.  This  is  the  case 
in  horse-chestnuts.  The  main  cluster  is  indeterminate,  bu1 
the  branches  are  determinate.    The  cluster  has  the  appear- 


195.   Determinate  or  cymose 
arrangement. — Wild  geranium 


124 


FLOWER-BRANCHES 


V 


Y: 


:■ 


197.  Forms  of  centripetal  flower-clusters, 
raceme;  2,  spike;  3,  umbel;  4,  head  or  anthodium;  5,  corymb. 


198.   Centripetal  inflorescence. 
0,  spadix;  7,  compound  umbel;  8,  catkin. 


199.  Centrifugal  inflorescence 
1,  cyme;  2,  scirpioid  cluster  (or  half  cyme 


FLOWER -CLUSTERS     AND    -STEMS 


125 


ance  of  a  panicle,  and  is  usually  so  called,  but  it  is  really  a 
thyrse.  Lilac  is  a  familiar  example  of  a  thyrse.  In  some 
cases,  the  main  cluster  is  determinate  and  the  branches  are 
indeterminate,  as  in  hydrangea  and  elder.  Such  clusters  also 
are  mixed  clusters. 

260.  Inflorescence. — The  mode  or  method  of  flower 
arrangement  is  known  as  the  inflorescence.  That  is,  the 
inflorescence  is  cymose,  corymbose,  paniculate,  spicate, 
solitary.     By   custom,    however, 

the  word  inflorescence  has  come 
to  be  used  for  the  flower-cluster 
itself  in  works  on  descriptive 
botany.  Thus  a  cyme  or  a 
panicle  may  be  called  an  inflo- 
rescence. It  will  be  seen  that 
even  solitary  flowers  follow  either 
indeterminate  or  determinate 
methods  of  branching. 

261.  The  Flower-stem.— The 
stem  of  a  solitary  flower  is  known 
as  a  peduncle;  also  the  general 
stem  of  a  flower-cluster.  The 
stem  of  the  individual  flower  in 
a  cluster  is  a  pedicel. 

262.  In  the  so-called  stemless  plants  (37)  the  peduncle 
may  arise  directly  from  the  ground,  or  crown  of  the  plant, 
as  in  dandelion,  hyacinth  (Fig.  186),  garden  daisy  (Fig.  200). 
This  kind  of  a  peduncle  is  called  a  scape.  A  scape  may  bear 
one  or  many  flowers.  It  has  no  foliage  leaves,  but  it  may  have 
bracts.  In  some  cases,  of  course,  the  flowers  are  sessile,  and 
in  others  very  nearly  sessile  (207).  In  Fig.  201,  the  little 
fruits  (following  the  flowers)  are  in  close  clusters  in  the  axils 
of  the  leaves. 

Review. — What  is  the  homology  of  flower-branches?  How  is  it 
that  flowers  arc  often  borne  in  clusters?    Explain  what  may  be  meant 


200.  Scapes  ol  the  I 
English  daisy. 


126 


FLOWER-BRANCHES 


by  a  solitary  flower.  What  are  the  two  types  of  flower-clusters?  What 
are  corymbose  clusters?  Define  raceme.  Spike.  Head  and  anthodium. 
Catkin.  Panicle.  Umbel.  Umbellet.  Corymb.  What  are  cymose 
clusters?  What  is  a  cyme?  Glomerule?  Contrast  indeterminate  and 
determinate  modes  of  branching.  Centripetal  and  centrifugal.  Explain 
mixed  clusters.  What  is  a  thyrse?  Define  peduncle,  pedicel  and  scape. 
Note. — In  the  study  of  flower-clusters,  it  is  well  to  choose  first 
those  that  are  fairly  typical  of  the  various  classes  discussed  in  the 
preceding  paragraphs.  As  soon  as  the  main  types  are  well  fixed  in  the 
mind,  random  clusters  should  be  examined,  for  the  pupil  must  never 
receive  the  impression  that  all  flower-clusters  follow  the  definitions  in 
books.  Clusters  of  some  of  the  commonest  plants  are  very  puzzling, 
but  the  pupil  should  at  least  be  able  to  discover  whether  the  inflores- 
cence is  determinate  or  indeterminate. 


201.  The  practically  sessile  axillary  clusters  of  coffee. 


CHAPTER   XX 

THE  PARTS   OF  THE   FLOWER 

263.  The  flower  exists  for  the  purpose  of  producing 
seed.  It  is  probable  that  all  its  varied  forms  and  colors 
contribute  to  this  supreme  end.  These  forms  and  colors 
please  the  human  fancy  and  make  living  the  happier,  but 
the  flower  exists  for  the  good  of  the  plant,  not  for  the  good 
of  man. 

264.  The  parts  of  the  flower  are  of  two  general  kinds — 
those  that  act  as  covering  and  protecting  organs,  and  those 
that  are  directly  concerned  in  the  'production  of  seeds.  The 
former  parts  are  known  as  the  floral  envelopes;  the  latter  as 
the  essential  organs. 

265.  Envelopes.— The  floral  envelopes  usually  bear  a 
close  resemblance  to  leaves.  These  envelopes  are  very  com- 
monly of  two  series  or  kinds — the  outer  and  the  inner.  The 
outer  series,  known  as  the  calyx,  is  usually  smaller  and  green. 
It  commonly  comprises  the  outer  cover  of 
the  flower-bud.   The  calyx  is  the  lowest 

whorl  in  Fig.  202. 
The  inner  scries, 
known  as  the  co- 
rolla, is  usually 
colored  and  more 
special  or  irregular 

cup  in  section.  inshape    than     the      203.  Flower  of  buttercup. 

calyx.  It  is  the  showy  part  of  the  flower,  as  a  rule.  The 
corolla  is  the  second  or  large  whorl  in  Fig.  202.  It  is  the 
large  part  in  Fig.  203. 

266.  The  calyx  may  be  composed  of  several  leaves.   Each 

(127) 


128 


PARTS     OF    THE     FLOWER 


204.  Gamosepalous 
and  gamopetalous 
flowers  of  sweet 
potato. 


leaf  is  a  sepal.  If  it  is  of  one  piece,  it  may  be  lobed  or  di- 
vided, in  which  case  the  divisions  are  called  calyx-lobes.  In 
like  manner,  the  corolla  may  be 
composed  of  petals,  or  it  may  be 
of  one  piece  and  variously  lobed. 

267.  A  calyx  of  one  piece  (as  in 
Fig.  204),.  no  matter  how  deeply 
lobed,  is  gamosepalous.  A  corolla 
of  one  piece  is  gamopetalous.  When 
these  series  are  of  separate  pieces 
(as  in  Fig.  202),  the  flower  is  said 
to  be  polysepalous  and  polypelalous. 
Sometimes  both  series  are  of  sep- 
arate parts,  and  sometimes  only 
one  of  them  is  so  formed.  The 
floral  envelopes  are  homologous 
with  leaves. 

268.  Sepals  and  petals,  at  least  when  more  than  three  or 
five,  are  each  in  more  than  one  whorl,  and  one  whorl  stands 
below  another  so  that  the  parts  over- 
lap. They  are  borne  on  the  expanded 
or  thickened  end  of  the  flower-stalk: 
this  end  is  the  torus.  In  Fig.  202  all 
the  parts  are  seen  as  attached  to  the 
torus.  This  part  is  sometimes  called 
a  receptacle,  but  this  word  is  a  com- 
mon-language term  of  several  mean- 
ings, whereas  torus  is  a  technical  word 
exclusively.  Sometimes  one  part  is 
attached  to  another  part,  as  in  the 
fuchsia  (Fig.  205)  in  which  the  petals 
are  borne  on  the  calyx-tube. 

269.  Essential  Organs.— The 
essential  organs  are  borne  within 
the  floral   envelopes  (when  envelopes 


205.  Flower  of  fuchsia 
in  section. 


STAMENS     AND     PISTILS 


129 


are  present).  They  are  of  two  series.  The  outer  series  is 
composed  of  the  stamens.  The  inner  series  is  composed  of 
the  pistils.  Stamens  and  pistils  are 
lomologous  with  leaves. 

;,  ^  270.  Stamens     bear 


200.  Pistil  of  garden  pea, 
the  stamens  being  pulled 
down  in  order  to  disclose 
it ;  also  a  section,  showing 
the  single  compartment. 


207.  Simple  pistils  of 
buttercup,  one  in 
longitudinal  section. 


the  pollen,  which  is 
made  up  of  a  large 
number  of  minute 
grains.  The  stamen  is 
of  two  parts,  as  readily 

seen  in  Figs.  202,  203,  205, — the  enlarged  terminal  part  or 

anther,  and  the  stalk  or  filament.    The  filament  is  often  so 

short  as    to   seem    to    be   absent,  and  the 

anther  is  then  said  to  be  sessile.   The  anther 

bears  the  pollen  grains.    It  is  made  up  of 

two  or  four  parts  (known  as  sporangia  or 

spore-cases),  which  burst  and  discharge  the 

pollen.      When    the     pollen    is    shed,    the 

stamen  dies. 

271.  Pistils  bear  the  ovules,  which  become 

seeds.    The  pistil  may  be  of 

one  part  or  compartment,  or 

of  many  parts.    The  different 

units  or  parts  of  which  it  is 

composed  are  carpels.    Each 

carpel  is  homologous  with  a 

leaf.    Each  carpel  bears  one 

or  more  seeds.     A  pistil  of 

one  carpel  is  simple;  of  two 

or  more  carpels,  compound. 

Usually  the  structure  of  the 

pistil  may  be  determined  by 

cutting  across  the  lower  or 

seed-bearing  part.    Figs.  206,  207,  208  explain.   A  flower  may 

contain  one  carpel  (simple  pistil)   as  the  pea   (Fig.   200); 


The  structure  of  a  plum  blossom. 
se.  sepals;  p.  petals;  sta.  stamens;  o. 
ovary;  s.  style;  si.  Btigma.    The  pistil 

consists  of  I  he  ovary,  style,  :nnl  Stigma. 

It  contains  the  seed  part.  The  stamens 
are  tipped  with  anthers,  in  which  the 
poUen  is  borne.  The  ovary,  <>,  ripens 
into  the  fruit. 


130 


PARTS     OF    THE     FLOWER 


several  separate  carpels  or  simple  pistils,  as  the 
buttercup;  or  a  compound  pistil,  as  the  St.  John's- 
wort  (Fig.  208). 

272.  The  pistil,  whether  simple  or  compound, 
has  three  parts:  the  lowest  or  seed-bearing  part, 
which  is  the  ovary;  the  stigma  at  the  upper 
extremity,  which  is  a  flattened  or  expanded 
surface  and  usually  roughened  or  sticky ;  the 
stalk-like  part  or  style,  connecting  the  ovary 
and  stigma.  Sometimes  the  style  is  appar- 
ently wanting, 
)ia?  and  the  stigma 
is  said  to  be 
sessile  o  n  the 
ovary.  These 
parts  are  shown 
in  the  fuchsia, 
Fig.  205.  The 
ovary  or  seed  vessel  is  at  a.  A  long  style,  bearing  a  large 
stigma,  projects  from  the  flower.  See, 
also,  Figs.  207  and  209. 

273.  Conformation  of  the  Flower. — 
A  flower  that  has  calyx,  corolla,  stamens 
and  pistils  is  said  to  be  complete;  all 
others  are  incomplete.  In  some  flowers 
both  the  floral  envelopes  are  wanting: 
such  are  naked.  When  one  of  the  floral 
envelope  series  is  wanting,  the  remaining 
series  is  said  to  be  calyx,  and  the  flower 
is  therefore  apetalous  (without  petals). 
The  knotweed  (Fig.  210),  smartweed, 
buckwheat,  elm  (Fig.  96),  are  examples. 

274.  Some  flowers  lack  the  pistils  but   „ 

r  211.  Flower     of     garden 

have    stamens:    these    are    staminate,      nasturtium.    Separate 

1,1,1  ,  .      .  petal  at  a.  The  calyx  is 

whether   the   envelopes   are   missing   or      prolonged  into  a  spur. 


210.  Knotweed,  a  very  common  but  inconspicuous  plant 
along  hard  walks  and  roads.  Two  flowers,  enlarged,  are 
shown  at  the  right.  These  flowers  are  very  small  and 
borne  in  the  axils  of  the  leaves. 


FORMS    OF    FLOWERS 


131 


212.  The  five  petals  of  the  pansy, 
detached  to  show  the  form. 


not.  Others  lack  the  stamens  but  have  pistils:  these  are 
pistillate.  Others  have  neither  stamens  nor  pistils:  these  are 
sterile  (snowball  and  hydrangea). 
Those  that  have  both  stamens  and 
pistils  are  -perfect,  whether  or  not 
the  envelopes  are  missing.  Those 
that  lack  either  stamens  or  pistils 
are  imperfect  or  diclinous. 
Staminate  and  pistillate 
flowers  are  imperfect  or 
diclinous. 

275.  Flowers  in  which 
the  parts  of  each  series 
are  alike  are 
said  to  be  regular 
(as  in  Figs.  202,  203,  204,  205).  Those  in  which 
some  parts  are  unlike  other  parts  of  the  same  series 
are  irregular.  The  irregularity  may  be  in  the  catyx, 
as  in  nasturtium  (Fig.  211);  in  the  corolla  (Figs. 
212,  213);  in  the  stamens  (compare  nasturtium, 
catnip  (Fig.  213)  sage,  or  in  the  pistils.  Irregularity 
is  most  frequent  in  the  corolla. 

Review. — What  is  the  flower  for?  What  are  the  two 
general  kinds  of  organs  in  the  flower?  What  is  the 
homology  of  the  flower-parts?  What 
are  floral  envelopes?  Calyx?  Sepals? 
Calyx-lobes?  Corolla?  Petals?  Corolla- 
lobes?  Gamosepalous  flowers?  Gamo- 
petalous?  Polysepalous?  Polypetalous? 
Define  torus.  What  arc  the  essential 
organs?  Stamen?  Filament?  Anther? 
Pollen?  Pistil?  Style?  Stigma?  Ovary? 
Carpel?  Define  a  complete  flower.  In 
what  ways  may  flowers  be  incomplete? 
Explain  perfect  and  imperfect  (or  di- 
clinous) flowers.  Define  regular  flowers. 
In  what  ways  may  flowers  be  irregular? 


%■/'?:  -'I.".. 

\~-t^dff£-^  Dissect- 

"""  inn  needle. 

214.   Improvised  1.,  natural 

stand  for  lens.  size. 


132 


PARTS     OF    THE     FLOWER 


Note. — One  needs  a  lens  for  the  examination  of  the  flower.    It  is 
best  to  have  the  lens  mounted  on  a  frame,  so  that  the  pupil  has  both 
hands  free  for  pulling  the  flower  in  pieces.    An  ordinary 
pocket  lens  may  be  mounted  on  a  wire  in  a  block,  as  in 
Fig.  214.    A  cork  is  slipped  on  the  top  of  the  wire  to  avoid 
injury  to  the  face.    The  pupil  should  be  provided  with  two 
dissecting  needles  (Fig.  215),  made  by  securing  an  ordinary 
needle  in  a  pencil-like  stick.     Another   convenient  arrange- 
ment is  shown  in  Fig.  216.    A  small  tin  dish  is  used  for  the 
base.     Into  this  a  stiff  wire  standard  is 
soldered.    The  dish  is  filled  with  solder, 
to  make  it  heavy  and  firm.    Into  a  cork 
slipped  on  the  standard,  a  crosswire  is 
inserted,  holding  on  the  end  a  jeweler's 
glass.     The  lens  can  be  moved  up  and 
down   and  sidewise.    This  outfit  can  be 
for   about   seventy-five  cents.     Fig.   217 
convenient    hand-rest    or    dissecting 
stand  to  be  used  under  this  lens.     It  may  be 
16  in.  long,  4  in.  high,  and  4  or  5  in.  broad. 
Various  kinds  of  dissecting  microscopes  are  on 
_,„    _.       ..  the  market    and  these  are  to  be  recommended 

216    Dissecting 

glass.  when  they  can  be  afforded. 


made 
shows 


217.   Dissecting  stand. 


CHAPTER   XXI 

FERTILIZATION   AND   POLLINATION 

276.  Fertilization. — Seeds  result  from  the  union  of  two 
elements  or  parts.  One  of  these  elements,  a  nucleus  of  a 
plant-cell,  is  borne  in  the  germinating  pollen-grain.  The 
other  element,  an  egg-cell,  is  borne  in  the  ovary.  The  pollen- 
grain  falls  on  the  stigma.  (Fig.  218.)  It  absorbs  water  or  the 
juices  exuded  by  the  stigma  and  grows  by  sending  out  a 
tube.  (Fig.  219.)  This  tube  grows  downward  through  the 
style,  absorbing  food  as  it  goes,  and  finally  reaches  the  egg- 
cell  in  the  interior  of  an  ovule  in 
the  ovary,  and  fertilization  by  the 
union  of  the  two  nuclei  takes  place. 
The  ovule  then  develops  into  a 
seed.  The  growth  of  the  pollen- 
tube  is  often  spoken  of  as  germi- 
nation of  the  pollen,  but  it  is 
not  germination  in  the  sense  in 
which  the  word  is  used  when 
speaking  of  seeds. 

277.  In   order    that 
the   pollen   may  grow, 

the  stigma  must  be  ripe.  At  this  stage,  the 
stigma  is  usually  moist  and  sometimes  sticky. 
The  pollen  is  held  by  the  mucilaginous  secre- 
tion on  the  stigma.  The  stigma  may  be  barbed 
or  feathery  and  hold  the  pollen  by  this  means. 
Observe  the  stigma  of  some  of  the  lilies.  In 
corn  the  "silk"  constitutes  the  style,  and  the 
stigma  is  feathery.  A  ripe  stigma  is  said  to  be 
(133) 


218.  B.  pollen  of  plum  escaping 
from  anther.  A,  pollen  germin- 
ating on  the  stigma.    Enlarged. 


219. 
Pollen  -  grain 
germinating. 
Magnified. 


134 


FERTILIZATION     AND     POLLINATION 


receptive.  The  stigma  may  remain  receptive  for  several  hours 
or  even  days,  depending  on  the  kind  of  plant,  the  weather, 
and  how  soon  pollen  is  received.  When  fertilization  takes 
place,    the    stigma  lJft($>     Vl 

dies.  Note  the  dried  fflj^lki-OillliM '/ -   fh„ 


3 


220. 
nther      of 

221. 
Barberry 

azalea, 
o  p  e  n  in  g 
by  termi- 
nal pores. 

stamen 
with    an- 
ther open- 
ing by  lids. 

222.   Flower  of  hollyhock;  proterandrous.    See  Fig.  223. 

end  of  the  "silk"  of  corn.    Observe,  also,  how  soon  the  petals 
wither  after  the  stigma  has  received  pollen. 

278.  Pollination. — The  transfer  of  the  pollen  from  anther 
to  stigma  is  known  as  pollination.  The  pollen  may  fall  of  its 
own  weight  on  the  adjacent  stigma,  or  it  may  be  carried 
from  flower  to  flower  by  wind,  insects  or  other  agents.  There 
may  be  self-pollination,  close-pollination  or  cross-pollination. 

In  self-pollination, 
the  pollen  that  falls 
on  the  pistil  is  de- 
rived from  the  same 
flower.  In  close- 
pollination,  the  pol- 
len may  be  derived 
from  different  flowers 
on  the  same  plant. 
In  cross-pollination, 
the  pollen  is  derived 
from  flowers  on  differ- 


FERTILIZATION     AND     POLLINATION 


135 


224.   Flower  of  larkspur. 


225.  Envelopes  of  a  larkspur.  There 
are  five  wide  sepals,  the  upper 
one  being  spurred.  There  are 
four  small  petals. 


ent  plants.  Fertilization  resulting  from  self-  or  close-pollina- 
tion is  close-fertilization.  Fertilization  resulting  from  cross- 
pollination  is  cross-fertilization.  In 
many  cases  cross-pollination  is 
essential  for  good  seed  or  fruit 
development.  Corn,  if  close-pol- 
linated, pro- 
duces imperfect  W  M 
ears.  Culti- 
vated plants 
frequently  ex- 
hibit decreased 
vigor  by  close- 
pollination. 

279.  Usually 
the  pollen  is  dis- 
charged by  the 
bursting  of  the  anthers.  The  commonest  method  of  discharge 
is  through  a  slit  on  either  side  of  the  anther.  (Fig.  218.)  Some- 
times it  discharges  through  a  pore  at  the  apex,  as  in  azalea 
(Fig.  220),  rhododendron,  huckleberry,  wintergreen.  In 
some  plants  a  part  of  the  anther  wall 
... Mjf/%  .  raises  or  falls  as  a  lid,  as  in  barberry  (Fig. 
'viffe^  221)>  Dmc  cohosh,  May  apple.  The  open- 
i)  ing  of  an  anther  (as  also  of  a  seed-pod)  is 
known  as  dehiscence.  When  an  anther  or 
seed-pod  opens  it  is  said  to  dehisce. 

280.  Most  flowers  are  so  constructed  as 
to  increase  the  chances  of  cross-pollination. 
The  commonest  means  of  insuring  cross- 
pollination  is  the  different  times  of  matur- 
ing of  stamens  and  pistils  in  the  same 
Mower.    In  most  cases  the  stamens  mature 

826.  Stamens  of  lark-     first:     the     flower     is     then     /irotrnuitlrous. 
spur,    surrounding      Ttri  ,  .    ...  _  .       _ 

the  pistils,  When  the  instils  mature  firsl  the  flower  is 


136 


FERTILIZATION     AND     POLLINATION 


proterogynous.  (Aner,  andr,  is  a  Greek  root  often  used,  in 
combinations,  for  stamen,  and  gyne  for  pistil.)  The  dif- 
ference in  time  of  ripening  may  be  an  hour  or  two,  or  it 
may  be  a  day.  The  ripening  of  the  stamens  and  pistils  at 
different  times  is  known  as  dichogamy,  and  flowers  of  such 
character  are  said  to  be  dichog- 
amous.  There  is  little  chance 
for  dichogamous  flowers  to  pol- 
linate themselves.  The  holly- 
hock is  proterandrous.  Fig.  222 
shows  a  flower  recently  ex- 
panded. The  center  is  occupied 
by  the  column  of  stamens.  In 
Fig.  223,  showing  an  older 
flower,  the  long  styles  are  con- 
spicuous. Many  flowers  are  im- 
perfectly k  dichogamous — some 
of  the  anthers  mature  simul- 
taneously with  the  pistils,  so 
that  there  is  chance  for  self-pol- 
lination in  case  foreign  pollen 
does  not  arrive.  Even  when  the 
stigma  receives  pollen  from  its 
own  flower,  cross -fertilization 
may  result. 

281.  Some  flowers  have  so 
developed  as  to  prohibit  self- 
pollination.  Very  irregular  flow- 
ers are  usually  of  this  cate- 
gory. Regular  flowers  usually  depend  on  dichogamy  and 
on  the  impotency  of  pollen  on  the  pistil  of  the  same  flower. 
Flowers  that  are  very  irregular  and  provided  with  strong 
perfume  are  usually  pollinated  by  insects.  Gaudy  colors 
probably  attract  insects  in  many  cases,  but  odor  appears  to 
be  a  greater  attraction.    The  insect  visits  the  flower  for  the 


MEANS    OF    POLLINATION 


U7 


228.  Staminate  catkins  of  oak.  The  pistil- 
late flowers  are  in  the  leaf  axils, 
and  not  shown  in  this  picture. 


nectar  (for  the  making  of  honey)  and  may  unknowingly 
carry  the  pollen.  Spurs  and  sacs  are  commonly  nectaries, 
but  in  spurless  flowers  the 
nectar  is  usually  secreted  in 
the  bottom  of  the  flower-cup. 
Fig.  224  shows  a  larkspur, 
and  the  envelopes  are  sepa- 
rated in  Fig.  225.  The  long 
spur  at  once  suggests  insect 
pollination.  The  spur  is  sepal. 
Two  hollow  petals  project 
into  this  spur,  apparently 
serving  to  guide  the  bee's 
tongue,  but  probably  of  no  sig- 
nificance. The  two  smaller  petals,  in  front,  are  differently 
colored  and  seem  to  serve  the  bee  in  locating  the  nectary. 
The  stamens  ensheath  the  pistils.  (Fig.  226.)  As  the  insect 
stands  on  the  flower  and  thrusts  his  head  into  its  center,  the 
envelopes  are  pushed  downward  and  outward  and  the  pistil 
,<>!^4&*,.  and  stamens  come  in  contact 

with  his  abdomen.  Since  the 
flower  is  proterandrous,  the 
pollen  which  the  pistils  receive 
from  the  bee's  abdomen  must 
come  from  another  flower.  Note 
a  somewhat  similar  arrange- 
ment in  the  toad-flax  or  butter- 
and-eggs.  (Fig.  227.)  Clover 
and  alfalfa  are  pollinated  by 
insects. 

282.  The  bee  is  perhaps  the 
most  efficient  of  all  insects  in 
distributing  pollen,  for  in  ad- 
dition to  carrying  away  pollen  accidentally  in  its  search  for 
nectar,  it  also  deliberately  gathers  pollen  from  the  flowers. 


229.  Catkins  of  a  willow.  A  staminate 
flower  is  shown  at  s.  and  a  pistil- 
late flower  at  p.  The  staminate 
and  pistillate  are  on  different 
plants. 


138 


FEETILIZATION     AND     POLLINATION 


In  certain  seasons,  moreover,  it  confines 
itself  to  a  single  species  of  plants.  Bees  are 
very  useful  to  the  fruit-grower,  wholly  aside 
from  the  honey  that  they  make  for  him. 

283.  Many  flowers  are  pollinated  by  the 
wind.  Such  flowers  produce  great  quantities 
of  pollen,  for  much  of  it  is  wasted.  They 
usually  have  broad  stigmas,  which  expose 
large  surfaces  to  the  wind.  They  are  usu- 
ally lacking  in  gaudy  colors  and  in  perfume. 
Grasses  and  pine  trees  are  typical  examples 
of  wind-pollinated  plants. 

284.  In  many  cases  cross-pollination  is 
insured  by  the  stamens  and  pistils  being 
in  different  flowers  (diclinous,  274).  When 
the  staminate  and  pistillate  flowers  are  on 
the  same  plant,  e.g.,  oak  (Fig.  228),  beech, 
chestnut, 


230.  Indian  corn,  a 
monoecious  plant, 
with  staminate 
flowers  borne  in 
the  tassel  and 
pistillate  flowers 
borne  in  the  ear. 


hazel,  walnut 
(Fig.  190), 
hickory,  the 
plant  is  mon- 
oecious ("in 
one  house")-  When  they  are 
on  different  plants  (poplar  and 
willow,  Fig.  229),  the  plant  is 
dioecious  ("in  two  houses"). 
Monoecious  and  dioecious 
plants  may  be  pollinated  by 
wind  or  insects,  or  other  agents. 
They  are  commonly  wind- 
pollinated,  although  willows 
are  often,  if  not  mostly,  in- 
sect-pollinated. Some  plants, 
as  rye,  insure  cross-pollination 


231.  Ear  of  maize,  product  of  the  pistil- 
late flowers  fertilized  by  pollen  borne 
in  the  tassel,  the  whole  enclosed  in  a 
husk  or  sheath. 


MEANS    OF    POLLINATION 


139 


#*p 


because  the  pollen  of  one  flower 
is  impotent  on  the  pistil  of 
that  flower.  Buckwheat  is 
another  such  plant. 

285.  The  corn  plants  are 
monoecious,  and  therefore  self- 
pollination  is  impossible.  The 
staminate  flowers  of  the  In- 
dian corn  are  in  a  terminal  A^'^M 
panicle  or  tasi 
The  pistillate 

dense  spike  (ear),  inclosed  in  a 
sheath  or  husk.  (Fig.  231.)  Each 
"silk"  is  a  style. 
Each  pistillate 
flower  may  produce 
a  kernel  of  corn. 
Sometimes  a  few 
pistil- 


flowers  are  in  a      ',**«*  *•'■"*' -^k1  wr  & 


232.  Panicle  or  tassel  of  a  sorghum  in 
blooming  time. 


late  flowers  are  borne  in  the  tassel 
and  a  few  staminate  flowers  on  the 
tip  of  the  ear.  In  sorghums,  broom- 
corn  and  kafirs  (Figs.  232,  233,  234), 
the  two  kinds  of  flowers  are  in  the 
same  cluster  or  tassel. 

286.  Although  most  flowers  are  of 
such  character  as  to  insure  or  increase 
the  chances  of  cross-pollination,  there 
are  some  in  which  crossing  is  abso- 
lutely forbidden.  These  flowers  are 
usually    borne    beneath    or    on    the 


233.   Head   or 
brush       of 

broom  -  corn     234.   Head     of 
at  seeding       one     of     the 

co'rnBri°s0m;    ^unseed!    ground,  and  they  lack   showy  colors 


and  perfumes.     They  are  known   as 
clr  i stoga mous  flowers  (meaning  "hidden 

peduncles  or       grownm  dry     fl^rs")-         The      P^t      haS      1U,nnal 


th?  ftiff    ffiTmlK    cleistogamous flowers (meairing  "hidden 


140 


FERTILIZATION     AND     POLLINATION 


235.  Hog-poanut,  showing  a  leaf,  and  a 
cleistogamous  flower  at  a. 


showy  flowers  that  may  be  insect-pollinated,  and  in  addi- 
tion is  provided  with  these  specialized  flowers.  Only  a  few 
plants  bear  cleistogamous  flowers.  Hog-peanut,  common  blue 
violet,  fringed  winter- 
green,  and  dalibarda 
are  the  best  subjects 
in  the  northern  states. 
Fig.  235  shows  a  cleis- 
togamous flower  of  the 
hog-peanut  at  a.  Above 
the  true  roots,  slender 
rhizomes  bear  these  flowers,  which  are  provided  with  a 
calyx  and  a  curving  corolla  that  does  not  open.    Inside  are 

the  stamens  and  pistils.  The 
pupil  must  not  confound 
the  nodules  on  the  roots  of 
the  hog-peanut  with  the 
cleistogamous  flowers:  these 
nodules  are  concerned  in  the 
appropriation  of  food.  Late 
in  summer  the  cleistogamous 
flowers  may  be  found  just 
underneath  the  mold.  They 
never  rise  above  the  ground. 
The  following  summer  one 
may  find  a  seedling  plant 
with  the  remains  of  the  old 
cleistogamous  flower  still 
adhering  to  the  root.  The 
hog-peanut  is  a  common  low 

3.  Common  blue   violet.     The  familiar  twiner      in      WOOds.        It  also 

flowers   are    shown,    natural   size.     The  Upnr<5    r„ppmp„    nf    email  r>Pfl_ 

corolla  is  spurred.    Later  in  the  season,  Dears    racemes    01    Small  pea- 

cleistogamous    flowers   are   often   borne  Jj^g     flowers.      CleistOgamOUS 
on  the  surface  of  the  ground.    A  small 

one   is  shown   at   o.     A   nearly   mature  flowers    USUally    appear  after 

pod    is  shown  at  b.    Both  a  and  b  are  ,  ,               ,                     a  ■ 

one-third  natural  size.  the    showy    flowers    have 


POLLINATION 


141 


passed.   They  seem  to  insure  a  crop  of  seed  by  a  met] 
that    expends 
(Fig.  236.) 

287.  There 
i  s  a  special 
and  peculiar 
structure  in 
the  peanut  or 
goober.  The 
flowers  are  of 
two    kinds. 

One  is  showy  and  staminate  (shown  uppermost 
in  Fig.  237) ;  and  one  is  small  and  pistillate,  and 
after  fertilization  is  thrust  downward  into  the 
earth  by  the  elongation  of  the  torus  and  flower- 
stem,  and  the  pods  ripen  underground.   (Fig.  238.) 

288.  Flowers  may  be  cross-pollinated  by  hand. 
One  may  carry  the  pollen  of  a  given  flower  to  the  pistils 
of  another  flower,  for  the  purpose  of  securing  seeds  that 
may  combine  some  of  the  characteristics  of  the  two  parents. 


238.  Peanut  pods  ripening  undergr 

In  this  case,  the  stamens  are  early  removed  from  the  flower 
to  be  pollinated  so  that  all  possibility  of  self-fertilization  is 
averted;   and  after  the  other  pollen  is  applied,  the  flower  is 


142 


FERTILIZATION     AND     POLLINATION 


protected  by  being  securely  covered  with  a  paper  bag.  (Fig. 
239.)  In  monoecious  plants,  if  the  staminate  flowers  are 
removed  or  covered  close-fertilization  is  prevented. 

Review. — What  is  fertilization?  Pollination? 
|t  iljjm  I  l/Jmm\  Pollen  germination?  What  is  a  receptive  stigma? 
§ff,l  How  is  pollen  discharged?  How  is  cross-pollina- 
tion secured?  Are  plants  benefited  by  cross-pol- 
lination? What  is  meant  by  impotent  pollen? 
What  do  you  understand  by  dichogamy?  Its  office? 
Is  it  frequent?  What  is  the  character  of  insect- 
pollinated  flowers?  Why  is  the  bee  an  effective 
insect  in  distributing  pollen?  What  is  the  sig- 
nificance of  irregularity  in  flowers?  Where  is  the 
nectar  borne?  What  are  monoecious  and  dioecious 
flowers?  Cleistogamous  flowers?  Why  may  flowers 
be  hand-pollinated? 

Note. — The  means  by  which  cross-pollination 
is  insured  are  absorbing  subjects  of  study.  It  is 
easy  to  give  so  much  time  and  emphasis  to  the 
subject,  however,  that  an  inexperienced  observer 
comes  to  feel  that  perfect  mechanical  adaptation 
of  means  to  end  is  universal  in  plants,  whereas 
it  is  not.  One  is  likely  to  lose  or  to  overlook  the 
sense  of  proportions  and  to  form  wrong  judgments. 

In  studying  cross-pollination,  one  is  likely  to  look  first  for  devices 
that  prohibit  the  stigma  from  receiving  pollen  from  its  own  flower,  but 
the  better  endeavor  is  to  determine  whether  there  is  any  means  to  insure 
the  application  of  foreign  pollen;  for  the  stigma  may  receive  both  but 
utilize  only  the  foreign  pollen.  Bear  in  mind  that  irregular  and  odd 
forms  in  flowers,  strong  perfume,  bright  colors,  nectar,  suggest  insect 
visitors;  that  inconspicuous  flowers  with  large,  protruding  stigmas 
and  much  dry  powdery  pollen  suggest  wind-transfer;  that  regular  and 
simple  flowers  depend  largely  on  dichogamy,  whether  wind-  or  insect- 
pollinated.   Most  flowers  are  dichogamous. 


239.  A  bag  covering  a 
pollinated  flower. 


CHAPTER  XXII 


PARTICULAR   FORMS   OF   FLOWERS 

289.  General  Forms. — Flowers  vary  wonderfully  in 
size,  form,  color,  and  in  shapes  of  the  different  parts.  These 
variations  are  characteristic  of  the  species  or  kind  of  plant. 
The  most  variable  part  is  the  corolla.  In  many  cases,  the 
disguises  of  the  parts  are  so  great  as  to  puzzle  botanists. 
Some  of  the  special  forms,  notably  in  the  orchids,  seem 
to  have  arisen  as  a  means  of  adapting 
the  flower  to  pollination  by  particular 
kinds  of  insects.  A  few  well-marked 
forms  are  discussed  below  in  order  to 
illustrate  how  they  may  differ  among 
themselves. 

290.  When  in  doubt  as  to  the  parts 
of  any  flower,  look  first  for  the  pistils 
and  stamens.  Pistils  may  be  distin- 
guished by  the  ovary  or  young  seed- 
case.  Stamens  may  be  distinguished 
by  the  pollen.  If  there  is  but  one 
series  in  the  floral  envelope,  the  flower  is  assumed  to  lack  the 

corolla:  it  is  apetalous  (273).  The  calyx,  however, 
in  such  cases,  may  look  like  a  corolla,  e.g.,  buck- 
wheat, elm,  sassafras,  smartweed,  knotweed. 
(Fig.  210.) 

291.  The  parts  of  a  flower  usually  have  a 
numerical  relation  to  each  other, — they  are 
oftenest  in  3's  or  5's  or  in  multiples  of  these 
numbers.  The  pistil  is  often  an  exception  to  this 
order,  however,  although  its  compartments  or 
(143) 


240.   Funnel  form  flower  of 
morning-glory. 


144 


PARTICULAR     FORMS     OF     FLOWERS 


carpels  may  follow  the  rule.    Flowers  on 
the  plan  of  5  are  said  to  be  pentamerous; 
those  on   the    plan   of   3    are  trimerous 
(merous  is  from  Greek,  signifying  "mem- 
ber").   In  descriptive  botanies 
these  words  are  often   written 
5-merous  and  3-merous. 

292.  The  corolla  often  as- 
sumes very  definite  or  distinct 
forms  when  gamopetalous.  It 
may  have  a  long  tube  with  a 
wide-flaring  limb,  when  it  is 
said  to  be  funnelform,  as  in 
morning-glory  (Fig.  240)  and  pumpkin.  If  the  tube  is 
very  narrow  and  the  limb  stands  at  right  angles  to  it,  the 


242.   Rotate  flowers  oi  potato. 


corolla  is  saberform,  as  in  phlox.  (Fig.  241.) 
very  short  and  the  limb  wide-spreading  and 
nearly  circular  in  outline,  the  corolla  is  rotate 
or  wheel-shaped,  as  in  potato.    (Fig.  242.) 

293.  A  gamopetalous  corolla  or  gamo- 
sepalous  calyx  is  often  cleft  in  such  way  as  to 
make  two  prominent  parts.  Such  parts  are 
said  to  be  lipped  or  labiate.  Each  of  the  lips 
or  lobes  may  be  notched  or  toothed.  In  5- 
merous  flowers,  the  lower  lip  is  usually  3-lobed 
and  the  upper  one  2-lobed.  Labiate  flowers 
are  characteristic  of  the  mint  family  (Fig. 
213),  and  the  family  therefore  is  called  the 
Labiatse.  (Properly,  labiate  means  merely 
lipped,  without  specifying  the  number  of  lips 
or  lobes;  but  it  is  commonly  used  to  designate 
2-lipped  flowers.)  Strongly  2-parted  poly- 
petalous  flowers  may  be  said  to  be  labiate; 
but  the  term  is  oftenest  used  for  gamopeta- 
lous corollas. 


If  the  tube  is 


243. 

Personate  flowers 
of  snapdragon. 


LABIATE    AND    LILY    FLOWERS 


145 


244.  Flower  of  trillium. 


294.  Labiate  gamopetalous 
flowers  which  are  closed  in 
the  throat  (or  entrance  to  the 
tube)  are  said  to  be  grinning 
or  personate  (personate  means 
masked,  or  person-like).  Snap- 
dragon is  a  typical  example 
(Fig.  243);  also  toad-flax  or 
butter  and  eggs  (Fig.  227),  and 
many  related  plants.  Personate 
flowers  usually  have  definite 
relations  to  insect  pollination. 
Observe    how   a   bee   forces   his 

head  into  the  closed  throat  of  the  toad-flax. 
295.  Lily    Flowers. — In 

plants  of  the  lily  family  (Lili- 

acese)  the  flowers  are  typically 

3-merous,  having  three  sepals, 

three  petals,  six  stamens  and 

a     3-carpelled     pistil.       The 

parts   in   the    different  series 

are  distinct  from  each  other 

(excepting   the   carpels),    and 

mostly  free  from  other  series. 

The  sepals  and  petals  are  so 

much  alike  that  they  are  dis- 
tinguished chiefly  by  position, 

and  for  this  reason  the  words 

calyx     and     corolla    are    not 

used,  but  the  floral  envelope  is 

called    the  'perianth   and   the 

parts  are  segments.  Flowers  of 

lilies  and  trilliums  (Fig.  244) 

answer  these  details.    Not  all 

flowers    in     the     lily    family 


245.  Papilionaceous  flowers. — 
Sweet  pea. 


146 


PARTICULAR     FORMS     OF     FLOWERS 


246.  Flowers  of  alfalfa, 
enlarged. 


247. 
Cassia  flower, 
showing  the 
separate 
keel  petals. 


answer  in  all  ways  to  this  description.    The  term  perianth 
is  used  in  other  plants  than  the  Liliacese. 

296.  Papilionaceous  Flowers. — In  the  pea  and  bean 
tribes  the  flower  has  a  special  form 
(Figs.  245,  246).  The  calyx  is  a  shal- 
low 5-toothed  tube.  The  corolla  is 
composed   of   four  pieces, — the   large 

expanded  part  at  the  back, 
known  as  the  standard  or 
banner;  the  two  hooded  side 
pieces,  known  as  the  wings; 
the  single  boat-shaped  part 
beneath  the  wings,  known  as 
the  keel.  The  keel  is  sup- 
posed to  represent  two  united 

petals,  since  the  calyx  and  stamens  are  in  5's  or  multiples 

of  5;   moreover,  it  is   of  two  distinct  parts  in  cassia  (Fig. 

247)  and  some  other  plants  of  the  pea  family.    Flowers  of 

the   pea   shape  are   papilionaceous 

(Latin  papilio,  a  butterfly). 

297.  Flowers  of  the  pea  and  its 
kind  have  a  peculiar  arrangement 
of  stamens.  The  stamens  are  10, 
of  which  9  are  united  into  a  tube 
which  incloses  the  pistil.  The  tenth 
stamen  lies  on  the  upper  edge  of  the 
pistil.  The  remains  of  these  sta- 
mens are  seen  in  Fig.  206.  The  sta- 
mens are  said  to  be  diadelphous  ("in 
two  brotherhoods")  when  united  into 
two  groups  as  in  this  case.  Stamens 
in  one  group  would  be  called  mona- 
delphous,    and    this    arrangement  24S-  Common  mallow,  a  trailing 

CT  plant    to   which   the  circle  of 

occurs    in    some    members   of   the       fruits,  a,  gives  the   names 

T  .  »         .,  "cheeses"  and    "shirt  button 

LeguminosaB  or  pea  family.  plant." 


THE    MALLOWS 


147 


249.  Flower  of  cotton.  Not< 

the  stamens;  also  the  in 
volucre   or  "square" 
the  bud. 


mi 


that    separate 
from  the  torus  when  the  fruit  is 
ripe.    Do  all  of  the  ovaries  de 
velop,  or  are  some  crowded  out 
in  the  struggle  for  exis- 
tence? 

299.  The  calyx  in 
such  flowers  is  often 
reinforced  by  bracts, 
which  look  like  an  extra 
calyx.  These  bracts  form 
an  involucre.  An  invo- 
lucre is  a  circle  or  whorl 
of  bracts  standing  just 
below  a  flower  or  a 
flower-cluster.  The  umbel 
of  -wild  carrot  (Fig.  194) 
has  an  involucre  below 
it.  A  large  family  of 
plants    known   as  the 


298.  Mallow  Flowers.— The 
flowers  of  the  mallow  family  are 
well  represented  in  single  holly- 
hocks (Figs.  222,  223)  and  in  the 
little  plant  (Fig.  248)  known  as 
"cheeses."  A  peculiar  structure 
is  the  part  formed  by  the  united 
filaments,  the  inclosed  styles  and 
the  ring  of  ovaries  at  the  bottom 
of  the  style-tube.  The  flower  is 
5-merous.  Count  the  ovaries. 
They  sit  on  the  torus,  but  are 
united  in  the  center  by  the  base 
of  the  style-tube,  which  forms 
cone-shaped  body       s^P a 

■/$. 


250.  A  lady's-slipper,  to  illustrate  the 
orchid  family. 


148 


PARTICULAR    FORMS    OF    FLOWERS 


Malvaceae,  or  Mallow  family,  has  flowers  similar  to  those  of 
the  hollyhock.  To  this  family  belong  marsh  mallow,  althea, 
okra,  cotton  (Fig.  249).  Observe  that  even  though  the 
hollyhock  is  a  great  tall-growing 
showy  plant  and  the  "cheeses"  is  a 
weak-  trailing  inconspicuous  plant, 
they  belong  to  the  same  family, 
shown  by  the  structure  of  the  flowers. 


251.  Jack-in-the-pulpit.  252.  Wild  aster,  with 

"Jack"  is  the  spadix;  six  heads,  each  con- 

the    "pulpit"    is    the  taining  several 

spathe.  florets. 


253.  Head  of  pasture 
thistle,  showing  the 
high  prickly  involucre. 


300.  Orchid  Flowers. — The  flowers  of  orchids  vary 
wonderfully  in  shape,  size  and  color.  Most  of  them  are 
specially  adapted  to  insect  pollination.  The  distinguish- 
ing feature  of  the  orchid  flower,  however,  is  the  union  of 
stamens  and  pistil  in  one  body,  known  as  the  column.  In 
Fig.  250  the  stemless  lady's-slipper  is  shown.  The  flower 
is  3-merous.  One  of  the  petals  is  developed  into  a  great 
sac  or  "slipper,"  known  as  the  lip.  Over  the  opening  of 
this  sac  the  column  hangs.  The  column  is  shown  in  detail: 
a  is  the  stigma;  d  is  an  anther,  and  there  is  another  similar 
one  on  the  opposite  side,  but  not  shown  in  the  picture;  b 


mowrrvoF 
ElMCOirFKniBRARY 


ORCHID    FLOWERS 


149 


is  a  petal-like  stamen,  which  does  not  produce  pollen.     In 
most  other  orchids  there  is  one  good  anther. 

301.  In  orchids  the  pollen  is  usually  borne  in  adherent 
masses,  one  or  two  masses  occupying  each  sporangium  of 
the  anther,  whereas,  in  most  plants  the  pollen  is  in  separate 
grains.  These  pollen-masses  are  known  technically  as  pollinia. 
Orchids  from  the  tropics  are  much  grown  in  choice  green- 
houses. Several  species  are  common  \\ 
in  woods  and  swamps  in  the  northern 
states  and  Canada. 


254.  Longitudinal    sec- 
tion of  thistle  head. 


255.  Floret  of 
thistle. 


256.  Cornflower  or  bachelor's  button, 
in  which  the  outer  florets  are  large 
and  showy. 


302.  Spathe  Flowers. — In  many  plants,  very  simple 
(often  naked)  flowers  are  borne  in  dense,  more  or  less  fleshy 
spikes,  and  the  spike  is  inclosed  in  or  attended  by  a  leaf, 
sometimes  corolla-like,  known  as  a  spathe.  The  spike  of 
flowers  is  technically  known  as  a  spadix.  This  type  of  flower 
is  characteristic  of  the  great  Arum  family,  which  is  chiefly 
tropical.  The  commonest  wild  representatives  in  the  North 
are  Jack-in-the-pulpit  or  Indian  turnip  (Fig.  251)  and  skunk 
cabbage.  In  the  former  the  flowers  are  all  diclinous  and 
naked.    The  pistillate  flowers  (comprising  only  a  1-loculed 


150 


PARTICULAR    FORMS    OF    FLOWERS 


ovary)  are  borne  at  the  base  of  the  spadix,  and  the  staminate 
flowers  (each  of  a  few  anthers)  are  above  them.  The  ovaries 
ripen  into  red  berries.  In  the  skunk  cabbage  all  the  flowers 
are  perfect  and  have  four  sepals.  The  common  calla  of 
greenhouses  is  a  good  example  of  this  type  of  inflorescence. 
303.  Compositous  Flowers. — The  head  (anthodium)  or 
so-called  "flower"  of  sunflower  and  whiteweed  and  daisy 
(Figs.  188,  189,  200),  thistle,  aster  (Fig.  252),  dandelion, 
daisy,  chrysanthemum,  goldenrod,  is  composed  of  several 
or  many  little  flowers,  or  florets.  These  florets  are  inclosed 
in  a  more  or  less  dense  and  usually 
green  involucre.  In  the  thistle  (Fig. 
253)  this  involucre  is  prickly.  A  longi- 
tudinal section  (Fig.  254)  discloses  the 
florets,  all  attached  at 
bottom  to  a  common 
torus,  and  densely 
packed  in  the  involucre. 
The  pink  tips  of  these 
florets  constitute  the 
showy  part  of  the  head. 
304.  Each  floret  of 
the  thistle  (Fig.  255)  is  a 
complete  flower.  At  a  is  the  ovary.  At  b  is  a  much-divided 
plumy  calyx,  known  as  the  pappus.  The  corolla  is  long- 
tubed,  rising  above  the  pappus,  and  is  enlarged  and 
5-lobed  at  the  top,  c.  The  style  projects  at  e.  The  five 
anthers  are  united  about  the  style  in  a  ring  at  d.  Such 
anthers  are  said  to  be  syngenesious. 

305.  These  are  the  various  parts  of  the  florets  of  the  Com- 
positae,  sometimes  known  as  the  Sunflower  family.  In  some 
cases  the  pappus  is  in  the  form  of  barbs,  bristles  or  scales, 
and  sometimes  it  is  wanting.  The  pappus,  as  we  shall  see 
later,  assists  in  distributing  the  seed.  Often  the  florets  are 
not  all  alike.   The  corolla  of  those  in  the  outer  circles  may  be 


257.  258.  Double  dahlias.  In  one,  the  florets 
have  developed  flat  rays.  In  the  other,  the 
florets  appear  as  inrolled  tubes. 


COMPOSITOUS   AND    GRASS    FLOWERS 


151 


developed  into  a  long,  strap-like 

or  tubular  part  and  the  corolla  of 

those  at  the  center  may  be  but  a 

short   tube.    The   head   then  has 

the  appearance  of  being  one  flower 

with  a  border  of  petals.    Of  such 

is  the  sunflower  (Fig.  188),  aster 

(Fig.   252),   bachelor's   button  or 

cornflower  (Fig.  256).    These  long 

corolla-limbs  are  called  rays.     In 

some   cultivated    composites,    all 

the  florets  may  develop  rays,  as  in 

the    dahlia   (Figs.  257,  258)    and 

chrysanthemum.    In  some  species, 

as  dandelion,  all  the  florets  natu- 
rally   have    rays.     Syngenesious 

arrangement    of    anthers    is    the 

most  characteristic  single  feature 
of  the  composites. 

306.  Grass  Flow- 
ers.—  The  flowers 
of  grasses  are  too 
difficult  for  the  be- 
ginner, but  if  the 
pupil  wishes  to  un- 
derstand them  he 
may    begin    with 

wheat  or  rye  or  barley,  which  are  members 
of  the  Grass  family.  The  "head"  or  spike  of 
wheat  is  made  up  of  flowers  and  bracts.  The 
flowers  are  in  little  clusters  or  spikelets  (often 
called    "breasts"  by  farmers).    One  of   the 

260.  Flower  of  rye/  gpikelets  is  shown  at  b,  in  Fig.  259.  Each 
stamens;  c,  pai'et-  spikelet  contains  from  1  to  4  flowers  or  florets. 
giume.°En1argecL    The  structure  of  the  flower  is  similar  to  that 


259.  Spikes  and  flowers  of  wheat, 
o.  beardless  wheat;  d,  bearded 
wheat;  6,  spikelet  in  bloom;  c, 
grain;  e,  single  spikelet  on  a 
mature  head.  The  bean  Is  in  d 
are  awns  on  the  Dowering 
glumes. 


152 


PARTICULAR    FORMS    OF    FLOWERS 


of  rye  (Fig.  260)  and  other  grasses.   The  pistil 
has  2   feathery  protruded   stigmas  (wind-polli- 
nated) shown  at  a,  Fig.  260.    There  are  3  sta- 
mens, b,  b,  b.     There  are  minute  scales  in  the 
base  of  the  flower  (not  shown  in  the  cut)  that 
probably  represent  true  floral  envelopes.    These 
are  lodicules.    The  larger  parts,  c,  d,  are  bracts. 
The  larger  one,  d,  is  the  flowering  glume,  and 
the  smaller,  c,  is  a  palet.    The  entire  spikelet  is 
also  subtended    by    two   bracts  or 
glumes;   these    are  the  two   lower- 
most   parts    in  b,    Fig.    259.     The 
glumes  of  the  spikelet,  and  flower- 
ing glumes  and  palets  of  the  flow- 
ers, constitute  the  chaff  when  wheat 
is  threshed.    Compare  barley,  Fig. 
261.   There  are  many  grass  plants  Barley  flower, 
with  large  florets    that    are   adap-       narge  " 
table  to  elementary  class  work,  as  millet  (Fig. 
262),  sorghums    (Figs.  232   to   234),  rice,  oats 
(Fig.  191),  and  a  number  of  big  lawn  grasses 
Maize  is  one  of  the  Grass  family. 

307.  Attachment  of  the  Flower  Parts.— The 
parts  of  the  flower  may  all  be  borne  directly 
on  the  torus,  or  one  part  may  be  borne  on 
another.  With  reference  to  the  pistil  or  ovary, 
the  stamens  and  envelopes  may  be  attached  in 
three  ways:  hypogynous,  all  free  and  attached 
under  the  ovary,  when  it  is  said  to  be  superior, 
as  in  Fig.  202;  perigynous,  or  attached  to  a 
more  or  less  evident  cup  surrounding  the  ovary, 
as  in  Fig.  209;  epigynous,  some  or  all  of  them 
apparently  borne  on  the  ovary,  when  it  is  said 
to  be  inferior,  as  in  Fig.  205. 
262nSiertman         308.  Double  Flowers.— Under  the  stimulus 


DOUBLE    FLOWERS 


153 


263.   Petals  arising  from  the  staminal  column  of  holly 
hock;  and  accessory  petals  in  the  corolla-whorl. 


of  cultivation  and  increased  food-supply,  flowers  tend  to 
become  double.  True  doubling  arises  in  two  ways,  morpho- 
logically: (1)  Petals 
may  appear  in  place 
of  stamens  and  pis- 
tils; (2)  adventitious 
or  accessory  petals 
may  arise  in  the 
circle  of  petals.  Both 
of  these  categories 
may  be  present  in 
the  same  flower,  as 
in  Fig.  263.  In  the 
full-double  holly- 
hock, the  petals  de- 
rived from  the  stam- 
inal column  are  shorter  and  make  a  rosette  in  the  center 
of  the  flower. 

309.  Other  modifications  of  flowers  are  sometimes  known 
as  doubling.  For  example,  double  dahlias  (Fig.  257),  chry- 
santhemums and  sunflowers  are  forms  in  which  the  disk 
flowers  have  developed  rays.  The  snowball  is  another  case. 
In  the  wild  plant 
(Fig.  264)  the  ex- 
ternal flowers  of 
the  cluster  are  large 
and  sterile.  In  the 
cultivated  plant 
(Fig.  265)  all  the 
flowers  have  be- 
come large  and 
sterile.  Hydrangea 
is  a  similar  example. 
Double  flowers  are 

■  •I     |       ,       i  ,       ..  264.  The  wild  or  orininal  form  of  the   snowball, 

likely  tO    be    Sterile.  Outer  flowers  larger. 


154  PARTICULAR    FORMS    OF    FLOWERS 

Review. — How  do  flowers  vary  in  form?  How  are  the  various 
parts  determined  in  disguised  flowers?  What  are  5-merous  and  3-merous 
flowers?  What  are  some  of  the  common  forms  of  gamopetalous  corollas? 
Describe  a  labiate  flower.  Personate.  Lily  flower.  Papilionaceous 
flower.  What  are  monadelphous  and  diadelphous  stamens?  Describe 
a  mallow  flower.  Orchid  flower.  Spathaceous  flower.  Compositoue 
flower.  If  grass  flowers  are  studied  in  class,  describe  one  of  them. 
What  do  you  understand  by  the  terms  hypogynous,  perigynous,  epi- 
gynous?  How  do  flowers  become  double?  What  is  meant  by  doubling 
in  compositous  flowers?    In  snowball  and  hydrangea? 


265.  Cultivated  snowball,  in  which  all  the 
flowers  in  the  cluster  have  become 
large  and  showy. 


CHAPTER  XXIII 

FRUITS 

310.  The  ripened  ovary,  with  its  attachments,  is  known 
as  the  fruit.  It  contains  the  seeds.  If  the  pistil  is  simple, 
or  of  one  carpel,  the  fruit  also  will  have  one  compartment. 
If  the  pistil  is  compound,  or  of  more  than  one  carpel,  the 
fruit  usually  has  an  equal  number  of  compartments,  although 
one  or  more  of  the  compartments  may  be  suppressed  as  the 
parts  grow.  The  compartments  in  pistil  and  fruit  are  known 
as  locules  (from  Latin  locus,  meaning  "a  place"),  or  cells. 

311.  The  simplest  kind  of 
fruit  is  a  ripened  1-loculed 
ovary.  The  first  stage  in  com- 
plexity is  a  ripened  2-  or  many- 
loculed  ovary.  Very  complex 
forms  may  arise  by  the  attach- 
ment of  other  parts  to  the 
ovary.  Sometimes  the  style 
persists  and  becomes  a  beak 
(mustard  pods,  dentaria,  Fig. 
266),  or  a  tail  as  in  clematis; 
or  the  calyx  may  be  attached 
to  the  ovary;  or  the  ovary 
may  be  imbedded  in  the  re- 
ceptacle, and  ovary  and  recep- 
tacle together  constitute  the 
fruit;  or  an  involucre  may  be- 
come a  part  of  the  fruit,  as 
possibly  in  the  walnut  and  hickory,  and  cup  of  the  acorn. 
The  chestnut  (Fig.  267)  and  the  beech  bear  a  prickly  invo- 

(155) 


266.    Dentaria,  or  tOOthwort,  in  fruit. 


156 


FRUITS 


lucre,  but  the  nuts,  or  true  fruits,  are  not  grown  faso  to  it, 
and  the  involucre  can  scarcely  be  called  a  part  of  the  fruit. 
A  ripened  ovary  is  a  pericarp.     A  pericarp  to  which  other 

parts    adhere    has 
been   called  an  ac- 
'•   cessory  or  reinforced 
fruit. 

312.  Some  fruits 
are  dehiscent,  or 
split  open  at  ma- 
turity (279)  and 
liberate  the  seeds; 
others  are  indehis- 
cent, or  do  not  open. 
A  dehiscent  peri- 
carp is  called  a  pod. 
The  parts  into 
which  such  a  pod 
breaks  or  splits  are  known  as  valves.  In  indehiscent  fruits 
the  seed  is  liberated  by  the  decay  of  the  envelope,  or  by 
the  rupturing  of  the  envelope  by  the  germinating  seed. 
Indehiscent  winged  pericarps  are  known  as  samaras  or  key- 
fruits  (consult  Chapter  XXIV).  Maple,  elm  (Fig.  97),  and 
ash  (Fig.  141)  are  examples. 

313.  Pericarps. — The   simplest  pericarp  is   a   dry,   one- 
seeded,  indehiscent  body.  It  is  known  as  an 
achene.  A  head  of  achenes  is  shown 
in  Fig.  268,  and  the  structure  is 
explained  in  Fig.   207. 
Achenes   may  be   seen 
in  buttercup,  hepatica, 
anemone,      smartweed, 
buckwheat. 

314.  A       l-l0CUled    268.  Achenes  269. 

.,.,,.  of   butter-      Follicle  of 

pericarp   that   dehisces      cup.  larkspur. 


267.  Chestnuts  are  ripened  ovaries.  They  are  borne  in  : 
prickly  involucre.  The  remains  of  the  catkin  of  stam- 
inate  flowers  is  seen  in  the  picture. 


270.  Young  follicles  of 
larkspur.  Normally, 
the  flower  has  5  pis- 
tils, but  some  are 
lost  in  the  struggle 
for  existence. 


FOLLICLES    AND    LEGUMES 


157 


271.  Follicles  of 
swamp  milk- 
weed, not  yet 
dehisced. 


along  the  front  edge  (that  is,  the  inner 
edge,  next  the  center  of  the  flower)  is  a 
follicle.    The  fruit  of  the  larkspur  (Fig. 
269)  is  a  follicle.    There  are  usually  five 
of  these  fruits  (sometimes  three  or  four) 
in    each    larkspur 
flower,    each    pistil 
ripening  into  a   fol- 
licle.   (Fig.   270.)    If 
these    pistils    were 
united,  a  single  com- 
pound   pistil    would 
be  formed.     Colum- 
bine, peony,    nine- 
bark   and   milkweed 
(Fig.  271)  also  have 

Legumes  of  perennial      follicles, 
or  everlasting  pea.  gjg       A     ^Q^led 

pericarp  that  dehisces  on  both  edges  is  a  legume.  Peas  and  beans 
are  typical  examples  (Figs. 
272,  273,  274):  in  fact,  this 
character  gives  name  to  the 
pea-family, — Leguminosae. 
Often  the  valves  of  the  legume 
twist  forcibly  and  expel  the 
seeds,  throwing  them  some 
distance.  Sometimes  (as  in 
peanut)  the  legume  does  not 
dehisce  of  itself,  even  though 
it  has  all  the  essential  struc- 
ture of  a  true  pod.  The  word 
pod  is  sometimes  restricted 
to  legumes,  but  it  is  better  to 
use  it  generically  (as  in  312) 
for  all  dehiscent  pericarps. 


276.  Capsules    of 

evening     prim-  278.  279. 

rose.      Loculic-  St.  John's-wort.  Loculicidal  pod. 
idal.                           Septieidal,  of  day-lily, 

(158) 


280.  Pyxis  of 
portulaca  or 
rose-moss. 


DEHISCENCE    OF    FRUITS 


159 


283. 
Basal  dehiscence  of 
campanula  capsule. 


316.  A  compound  pod — dehiscing  pericarp  of  two  or 
more  carpels — is  a  capsule.  (Pigs.  275,  276.)  There  are 
some  capsules  of  one  locule,  but  they  may  have  been  com- 
pound when  young  (in  the  ovary  stage) 
and  the  partitions  may  have  vanished. 
Sometimes  one  or  more  of  the  carpels  are 
uniformly  crowded  out  by  the  exclusive 
growth  of  other  carpels.  (Fig.  277.)  The 
seeds  or  parts  that  are  crowded  out  are  said 
to  be  aborted. 

317.  There  are  several  ways  in  which 
capsules  dehisce  or  open.  When  they  break 
along  the  partitions  (or 
septa),  the  mode  is  known  as  septicidal 
dehiscence;  Fig.  278  shows  it.  In  septi- 
cidal dehiscence,  the  fruit  sepa- 
rates into  parts  representing  the 
original  carpels.  These  carpels 
may  still  be  entire,  and  they  then 
dehisce  individually,  usually 
along  the  inner  edge  as  if  they 
were  follicles.  When  the  com- 
partments split  in  the  middle, 
between  the  partitions,  the  mode  is  lo- 
cidicidal  dehiscence.  (Fig.  279.)  In  some 
cases  the  dehiscence  is  at  the  top,  when 
it  is  said  to  be  apical  (although  several 
modes  of  dehiscence  are  here  included). 
When  the  whole  top  comes  off,  as  in 
purslane  and  garden  portulaca  (Fig.  280), 
the  pod  is  known  as  a  pyxis.  In  some 
cases  apical  dehiscence  is  by  means  of 
a  hole  or  clefts.  (Fig.  281.)  In  pinks  and 
their  allies  the  dehiscence  does  not 
extend  much  below  the  apex.  (Fig.  282.)        '  '  0f  cataip». 


; 


160 


FRUITS 


h^ 


Dehiscence  may  be  basal.  (Fig.  283.)  Two-loculed  capsules 
that  resemble  legumes  in  external  appearance  are  those  of 
catalpa  and  trumpet-creeper.'  (Figs.  284,  285.) 

318.  The   peculiar   capsule    of    the    mustard 
family,  or  Cruciferae,  is  known  as  a  silique  when 
it  is  distinctly  longer  than  broad  (Fig.  266),  and 
a  silicle  when  its  breadth  nearly  equals  or  exceeds 
its  length.   (Fig.  286.)    A  cruciferous  cap- 
sule is  2-carpelled,  usually  with  a  thin 
partition,  each  locule  containing  seeds  in 
one  or  two  rows.    The  two  valves  detach 
from  below  upwards.    Cabbage,  mustard, 
cress,   shepherd's  purse,  sweet  alyssum, 
wallflower,  honesty,  are  examples. 

319.  The  pericarp  may  be  fleshy  and 
indehiscent.  A  pulpy 
pericarp  with  several  or 

_,  many  seeds  is  a  berry. 
^    (Fig.  287.)    To  the  hor- 
ticulturist a  berry  is  a   285-  Lai-ge  2-vaived 

pods  or  capsules  of 
Small,    SOlt,   edible   IrUlt,        tecoma  or  trumpet- 
without  particular  reference  to  its  struc-       creePer- 
ture.      The  botanical   and   horticultural   conceptions  of  a 

berry  are,  therefore, 
unlike.  In  the  botan- 
ical sense,  gooseber- 
ries, currants,  grapes, 
tomatoes,  potato- 
balls  and  even  egg- 
plant fruits  (Fig.  288) 
are  berries;  strawber- 
ries, raspberries, 
blackberries  are  not. 
320.  A  fleshy  peri- 
carp  containing  one 


286.  Shepherd's  purse. 
Silicle. 


COMBINED    FRUITS 


161 


%it* 


Eggplant  fruits.    Ej 
large  berries. 


relatively  large  seed  or  stone  is  a  drupe.   Examples  are  plum 

(Fig.  289),  peach,  cherry,  apricot,  olive.    The  walls  of  the 

pit    in    the    plum,    peach     and 

cherry  are  formed  from  the  inner 

coats  of  the  ovary,  and  the  flesh 

from  the  outer  coats.   Drupes  are 

also  known  as  stone-fruits. 

321.  Fruits  that  are  formed  by 
the  subsequent  union  of  separate 
pistils  are  aggregate  fruits.  The 
carpels  in  aggregate  fruits  are 
usually  more  or  less  fleshy.  In 
the  raspberry  and  blackberry  flower,  the  pistils  are  essenti- 
ally distinct,  but  as  the  pistils  ripen  they  cohere  and  form 

one  body.  (Fig.  290.)  Each  of  the 
carpels  or  pistils  in  the  raspberry  and 
blackberry  is  a  little  drupe,  or  drupelet. 
In  the  raspberry  the  entire  fruit  sep- 
arates from  the  torus,  leaving  the  torus 
on  the  plant.  In  the  blackberry  and 
dewberry  the  fruit  adheres  to  the  torus, 
and  the  two  are  removed  together 
when  the  fruit  is  picked. 

322.  Accessory  Fruits. — When  the  pericarp  and  some 
other  part  grow  together,  the  fruit  is  said  to  be  accessory  or 
reinforced  (311).  An  example  is 
the  strawberry.  (Fig.  291.)  The 
edible  part  is  a  greatly  enlarged 
torus,  and  the  pericarps  are 
achenes  imbedded  in  it.  These 
achenes    are    commonly    called 

„ gg/Jg  29°-   Aggregate  fruits  of  raspberry. 

323.  Various  kinds  of  reinforced  fruits  have  received 
special  names.  One  of  these  is  the  hip,  characteristic  of  roses. 
(Fig.  292.)    In  this  case,  the  torus  is  deep  and  hollow,  like  an 


289.  Plum.    Example  of  a 
drupe. 


162 


FRUITS 


urn,  and  the  separate  achenes  are  borne  inside  it.  The  mouth 
of  the  receptacle  may  close,  and  the  walls  sometimes  become 
fleshy:  the  fruit  may  then  be  mistaken  for  a  berry. 

324.  The  reinforced 
fruit  of  the  pear,  apple, 
and  quince  is  known  as  a 
pome.  In  this  case  the 
five  united  carpels  are 
completely  buried  in  the 
hollow  torus,  and  the  torus 
makes  most  of  the  edible 
part  of  the  ripe  fruit,  while 
the  pistils  are  represented 

291.  Strawberries.    The  edible  part  is  torus.  Uv    |V>p     OOrP        ( Fiff     293  ) 

Fig.  294  shows  the  apple  in  bloom;  Fig.  295  shows  young 
fruits,  only  one  having  formed  in  each  cluster.  In  the  lower 
left-hand  flower  of  Fig.  294,  note  that  the  sepals  do  not  fall. 
Observe  the  sepals  on  the  top  of  the  torus  (apex  of  the 
fruit)  in  Fig.  295.  In  the  plum  flower  (Fig.  209),  note  that 
the  pistil  sits  free  in  the  hollow  torus:  imagine  the  pistil 
and  torus  grown  together,  and  something  like  a  pome 
might  result. 

325.  The  reinforced  fruit  of  pumpkin,  squash 
(Fig.  296),  melon  and  cucumber  is  a  pepo.    The 
outer  wall  is  torus,  but  the  sepals  do  not  persist, 
and  the  fruit  is  normally  3-loculed  (although  the 
partitions  may    disappear   as   the 
fruit  ripens).    The  maypop,  one  of 
the  passion  flowers  growing  wild  in 
the  southern  states,  has  a  similar 
structure. 

326.  Gymnospermous  Fruits.—  292-  mP  of  rose 
In  pines,  spruces  and  their  kin,  there  is  no  fruit  in  the 
sense  in  which  the  word  is  used  in  the  preceding  pages, 
because  there  is  no  ovary.     The  ovules  are  naked  or  uncov- 


293.  Diagram  of 
a  pear.  The 
receptacle  is 
o,  and  the 
pericarp  6. 


294.  Apple  flowers. 


295.  Young  apple  fruits. 

(163) 


164 


FRUITS 


296.  Pepo  or  squash. 


ered,  in  the  axils  of  the  scales  of  the  young  cone,  and  they 

have  neither  style  nor  stigma.  The  pollen  falls  directly  tm 
the  mouth  of  the  ovule.  The  ovule 
ripens  into  a  seed  (Fig.  297)  which  is 
usually  winged.  Because  the 
ovule  is  not  borne  in  a  sac 
or  ovary,  these  plants  are 
called  gymnosperms  (Greek  for 
"naked  seeds").  AH  the  true 
cone-bearing  plants  are  of  this 
class;  also  certain  other 
plants  as  red  cedar,  juniper, 

yew.     The  plants  a*re  monoecious  or  sometimes   dioecious. 

The   staminate    flowers    are   mere    naked    stamens    borne 

beneath  scales,  in  small  yellow  catkins  which 

soon  fall.    The   pistillate  flowers  are  naked 

ovules  beneath  scales  on  cones  which  persist. 

(Figs.  298,  299.) 

Review. — What  is  a  fruit,  as  understood  by  the 
botanist?  What  is  a  locule?  What  are  simple,  com- 
pound and  accessory  or  reinforced  fruits?  Define 
pericarp.    Pod.    What  are  dehiscent  and  indehiscent 

fruits?    What  is  a  samara  or  key-fruit? 

Define  achene.  Follicle.  Legume.  Cap- 
sule. Explain  septicidal  and  loculicidal 

dehiscence.     Apical   dehiscenc.     Basal 

dehiscence.    What  is  a  pyxis?   Silique? 

Silicle?     Berry?      Drupe?      Drupelet? 

Explain  an    aggregate   fruit.     Explain 

the    fruit  of    strawberry,  rose,  apple, 

squash.     What  is   the  fruit   of   pines 

and  spruces? 

Note. — Fully   mature    fruits    are    best    for    study, 
particularly   if   it   is    desired    to    see    dehiscence.     For 
comparison,   pistils  and  partially  grown    fruits   should 
299.     Pistillate    be    had    at    the    game    timei     jf   the   fruits   are  not  ripe 
cone  of  white  ,   ,  .  ,  ,         ,         ,  .     xl  , 

pine.  enough  to  dehisce,  they  may  be  placed  in  the  sun  to  dry. 


298.  Pistillate  cone 
of  Norway  spruce. 
This  tree  is  one  of 
the  commonest  of 
planted  ever- 
greens. 


TABLE    OF    FRUITS 


165 


In  the  school  it  is  well  to  have  a  collection  of  fruits  for  study.    The 
specimens  may  be  kept  in  glass  jars. 

The  following  diagram  will  aid  the  pupil  to  remember  some  of  the 
fruits  to  which  particular  names  have  been  given.  He  must  be  warned, 
however,  that  the  diagram  does  not  express  the  order  of  evolution  of 
the  various  kinds.  He  should  also  remember  that  there  are  many 
common  fruits  that  answer  to  no  definition,  and  these  should  be  studied 
and    compared    with  the  forms  that    have  received    definite  names: 


Dry  -pericarps . 


Simple 


(achene  (indehiscent). 
follicle  (dehiscent), 
legume  (dehiscent). 


septicidal  dehiscence. 
Pericarps  ,  Compound  -  loculicidal  dehiscence, 

(capsule)      (^apical  dehiscence. 

f  [Pyxis. 

berry. 
drupe, 
drupelet. 
A  ggregate  pericarps 


Accessory  Fruits 


(strawberry. 
hip. 
pome, 
pepo. 


Gymnospermous  or  Cone  Fruits. 


CHAPTER  XXIV 


DISPERSAL    OF   SEEDS 

327.  It  is  to  the  advantage  of  the  plant  to  have  its  seeds 
distributed  as  widely  as  possible.  It  has  a  better  chance  of 
surviving  in  the  struggle  for  existence. 
It  gets  away  from  competition.  Many 
seeds  and  fruits  are  of  such 
character  as  to  increase 
their  chances  of  wide  dis- 
persal. The  commonest 
means  of  dissemination  may 
be  classed  under  four  heads: 
explosive  fruits ;  transporta- 
tion by  wind;  transporta- 
tion by  birds;  transportation 
as  burs. 

328.  Explosive  Fruits. — 
Some  pods  open  with  explosive  force  and  scatter 
the  seeds.  Even  beans  and  everlasting  peas 
(Fig.  272)  do  this.  More 
marked  examples  are  the 
locust,  witch  hazel,  gar- 
den balsam,  wild  jewel- 
weed  or  impatiens 
(known  also  as  "touch- 
me-not"),  violet,  and  the  oxalis.  (Fig. 
300.)  The  oxalis  is  common  in  several 
species  in  the  wild  and  in  cultivation. 
One  of  them  is  known  as  wood  sorrel. 
Fig.  300  shows  the  common  yellow 
(166) 


300.  Explosive  fruits  of 
oxalis.  An  exploding 
pod  is  shown  at  c.  The 
dehiscence  is  shown  at 
b.  The  structure  of  the 
pod  is  seen  at  a. 


302. 

Wind-blown  fruits 

of  dandelion. 


WIND-TRAVELERS 


167 


303.  The  expanding  balloons  of  the  milkweed. 


oxalis.  The  pod  opens  loculicidally.  The  elastic  tissue  sud- 
denly contracts  when  dehiscence  takes  place,  and  the  seeds 
are  thrown  violently.  The  fruit  of  the  squirting  cucumber 
discharges  the  seeds  with  great  force,  throwing  them  many 


168 


DISPERSAL    OF    SEEDS 


feet.    This  plant  is  easily  grown  in  a  gar- 
den (procure  seeds  of  seedsmen). 

329 .  Wind  -  travelers.  —  Wind-  trans- 
ported seeds  are  of  two  general  kinds — 
those  that  are  provided  with  wings,  as  the 
flat  seeds  of  catalpa  (Fig.  301)  and  cone- 
bearing  trees  (Fig.  297)  and  the  samaras 
of  ash,  elm,  tulip-tree,  ailanthus  and 
maple;  those  that  have  feathery  buoys  or 
parachutes  to  enable  them  to  float  in  the 
air.  Of  the  latter  kind  are  the  fruits  of 
many  composites,  in  which  the  pappus  is 
copious  and  soft.  Dandelion  (Fig.  302) 
and  thistle  (Fig.  256)  are  examples.  The 
silk    of     the 


304.  Head  of  cat-tail  in 
late  fall.  The  fruits 
are  carried  in  the  late 
autumn  winds. 


Drupes  of  the  black  haw,  loved 
of  robins  in  winter. 


milkweed  (Fig, 
303)  has  a  similar  office,  and  also 
the  wool  of  the  cat-tail.  (Fig. 
304.)  Recall  the  cottony  seeds 
of  the  willow  and  poplar. 

330.  Dispersal  by  Birds — 
Seeds  of  berries  and  of  other 
small  fleshy  fruits  are  carried  far 
and  wide  by  birds.  The  pulp  is 
digested,  but  the  seeds  are  not 
injured.  Note  how  the  cherries, 
raspberries,  blackberries  and 
Juneberries  spring  up  in  the 
fence-rows,  where  the  birds  rest. 
Some  berries  and  drupes  persist 
far  into  winter,  when  they  supply 
food  to  cedar-birds,  robins  and 
the  winter  birds.  (Fig.  305.) 
Red  cedar  is  distributed  by  birds. 
Many   of    the   pulpy  fruits   are 


BUR-TRAVELERS 


169 


306.    The    cow    is   carrying 
burdocks. 


agreeable  as  human  food,  and  some  of  them  have  been  greatly- 
enlarged  or  "improved"  by  the  arts  of  the  cultivator. 

331.  Burs. — Many  seeds  and  fruits  bear  spines,  hooks, 
and  hairs  that  adhere  to  the  coats  of 
animals  (Fig.  306)  and  to  clothing. 
The  burdock  has  an  involucre  with 
hooked  scales,  containing  the  fruits 
inside.  The  clotbur  is  also  an  in- 
volucre. Both  are  compositous  plants, 
allied  to  thistles,  but  the  whole  head, 
rather  than  the  separate  fruits,  is 
transported.  In  some  compositous 
fruits  the  pappus  takes  the  form  of 
hooks  and  spines,  as  in  the  "Spanish 
bayonets"  and  "pitchforks."  Fruits 
of  various  kinds  are  known  as  "stick- 
tights,"  as  of  the  agrimony  and 
hound's  tongue.  Those  who  walk  in  the  woods  in  late 
summer  and  fall  are  aware  that  plants  have  means  of 
disseminating  themselves.  (Fig.  307.)  If  it  is  impossible 
to  identify  the  burs  which  one  finds  on  clothing,  the  seed 
may  be  planted  and  specimens  of  the  plant  may  then  be 
mA      />,  jA,     groAvn. 

Review. — What  advantage  is  it  to  the  plant  to 

have  its  seeds  widely  dispersed?    What  are  the  leading 

ways  in  which  fruits  and  seeds  are  dispersed?     Name 

some  explosive  fruits.    Describe  wind-travelers,    What 

seeds   are   carried  by  birds?     Describe  any  bur  with 

t'hich  you  are  familiar. 

Note. — This   lesson    will    suggest    other 

;ways  in  which  seeds  are  transported.    Nuts 

are  buried  by  squirrels  for  food,  but  if  they 
307.  Stealing  a  ride.  &re  nQt  eaten   1h(iy  may  gn)w      Th(l  S(,(.,,s  ,,,- 

many  plants  are  blown  on  the  snow.  The  old  stalks  of  weeds,  standing 
through  the  winter,  may  serve  to  disseminate  the  plant.  Seeds  are 
carried  by  water  down  the  streams  and  along  shores.    About  woollen 


wmw 


170  DISPERSAL    OF    SEEDS 

mills  strange  plants  often  spring  up  from  seeds  brought  in  the  fleeces. 
Sometimes  the  entire  plant  is  rolled  for  miles  before  the  winds.  Such 
plants  are  "tumble-weeds."  Examples  are  Russian  thistle  (Fig.  113), 
hair-grass  or  tumblegrass  (Panicum  capillare),  cyclone  plant  (Cyclo- 
loma  platyphyllum),  and  white  amaranth.  About  seaports  strange 
plants  are  often  found,  having  been  introduced  with  the  earth  that 
is  used  in  ships  for  ballast.  These  plants  are  usually  known  as  "bal- 
last plants."    Most  of  them  do  not  persist  long. 

In  some  way,  the  seeds  of  every  plant  are  dispersed,  some  far 
and  some  near:  discover  these  ways  for  any  plant  that  you  know. 


CHAPTER  XXV 

GERMINATION 

332.  The  Seed. — We  have  found  (276)  that  as  a  result 
of  fertilization  a  seed  is  formed.  The  seed  contains  a  minia- 
ture plant  or  embryo.  The  embryo  usually  has  three  parts 
that  have  received  names:  the  little  stemlet  or  caulicle; 
the  seed-leaf  or  cotyledon  (usually  1  or  2);  the  bud  or  plumule 
lying  between  or  above  the  cotyledons.  These  parts  are  well 
seen  in  the  common  bean  (Fig.  308),  particularly  when  the 
seed  has  been  soaked  for  a  few  hours. 
One  of  the  large  cotyledons — comprising  half 
of  the  bean — is  shown  at  r.  The  caulicle  is 
at  c.  The  plumule  is  at  a.  The  cotyledons  are  308  Part9  of°the 
attached  to  the  caulicle  at  /:  this  point  is  the  bean-  r<  cotyie- 
first  node,  and  the  plumule  is  at  the  second  a,  plumule;  /, 
node.  firstnode- 

333.  Every  seed  is  provided  with  food,  to  support  the 
germinating  plant.  Commonly  this  food  is  starch.  The 
food  may  be  stored  in  the  cotyledons,  as  in  bean,  pea,  squash ; 
or  outside  the  cotyledons,  as  in  castor  bean,  pine,  Indian 
corn.  When  the  food  is  around  the  embryo,  it  is  usually 
called  endosperm. 

334.  The  embryo  and  endosperm  are  inclosed  within  a 
covering  made  of  two  or  more  layers  and  known  as  the  seed- 
coats.  Over  the  point  of  the  caulicle  is  a  minute  hole  or  a 
thin  place  in  the  coats  known  as  the  micropyle.  This  is 
the  point  at  which  the  pollen-tube  entered  the  forming 
ovule  and  through  which  the  caulicle  breaks  in  germination. 
The  micropyle  is  shown  at  m  in  Fig.  309.  The  scar  where 
the  seed  broke  from  its  funiculus  or  stalk  is  the  hilum.    It 

(171) 


172  GERMINATION 

occupies  a  third  of  the  length  of  the  bean  in  Fig.  309.  The 
hilum  and  micropyle  are  always  present  in  seeds,  but  they 
are  not  always  close  together.  In  many  cases  it  is  difficult 
to  identify  the  micropyle  in  the  dormant  seed,  but  its  location 
^  is  at  once  shown  by  the  protruding  caulicle 
as  germination  begins.  Opposite  the  micropyle 
in  the  bean  (at  the  other  end  of  the  hilum)  is 
External  parts  of  an  elevation  known  as  the  raphe.  This  is 
bean.  formed  by  a  union  of  the  funiculus  or  seed- 

stalk  with  the  seed-coats,  and  through  it  food  was  transferred 
for  the  development  of  the  seed,  but  it  is  now  functionless. 

335.  Seeds  differ  wonderfully  in  size,  shape,  color  and 
other  characteristics.  They  also  vary  in  longevity.  These 
characteristics  are  peculiar  to  the  species  or  kind.  Some 
seeds  maintain  life  only  a  few  weeks  or  even  days,  whereas 
others  will  "keep"  for  ten  or  twenty  years.  In  special  cases, 
seeds  have  retained  vitality  longer  than  this  limit,  but  the 
stories  that  living  seeds,  several  thousand  years  old,  have 
been  taken  from  mummies  are  unfounded.  Oats  do  not 
retain  their  vitality  for  more  than  a  year  or  two.  Seed  of 
alfalfa  may  retain  its  vitality  for  eight  years  or  more.  The 
condition  of  storage  of  the  seed  is  an  important  factor  in 
the  retention  of  seed  vitality.  Moisture  is  especially  dele- 
terious; a  dry  atmosphere  of  the  storage  room  is  necessary 
for  maintaining  the  vigor  of  the  seed. 

336.  Germination. — The  embryo  is  not  dead;  it  is  only 
dormant.  When  supplied  with  moisture,  warmth,  and  oxy- 
gen (air),  it  awakes  and  grows:  this  growth  is  germination. 
The  embryo  lives  for  a  time  on  the  stored  food,  but  grad- 
ually the  plantlet  secures  a  foothold  in  the  soil.  The  roots 
absorb  and  the  leaves  elaborate  food  and  the  seedling  is  inde- 
pendent with  respect  to  its  food  supply.  When  the  plantlet 
is  finally  able  to  shift  for  itself,  germination  is  complete. 

337.  The  germinating  seed  first  absorbs  water,  and 
swells.    The  starch  and  other  stored  foods  are  transformed 


THE     PROCESS     OF     GERMINATION 


173 


310.  The  young  roots  are  not  able  to 
gain  a  foothold. 


into  soluble  products.  They  are  digested,  so  to  speak,  and 
made  available  for  assimilation  by  the  protoplasm.  Germi- 
nate barley.  Note  how  sweet 
it  is  to  the  taste.  Compare  it 
with  the  ungerminated  barley. 
Do  likewise  with  corn  and 
wheat.  What  is  the  source  of 
the  sugar?  The  seed-coats  are 
ruptured,  the  caulicle  and 
plumule  emerge.  In  this  pro- 
cess, the  seed  respires  freely, 
giving  off  carbon  dioxid  (C02). 
Fill  a  tin  box  or  large-necked 
bottle  with  dry  beans  or  peas,  then  add  water;  note  how 
much  they  swell.  Secure  two  fruit-jars.  Fill  one  of  them 
a  third  full  of  beans  and  keep  them 
moist.  Allow  the  other  to  remain  empty. 
In  a  day  or  two  insert  a  lighted  splinter 
or  taper  into  each.  In  the  empty  jar 
the  taper  burns:  it  contains  oxygen. 
In  the  seed-jar  the  taper  goes  out:  the 
air  has  been  replaced  by  carbon 
dioxid.  Usually  there  is  a  percepti- 
ble rise  in  temperature  in  a  mass 
of  germinating  seeds. 

338.  The  caulicle  usually  elon- 
gates, and  from  its  lower  end  roots 
are  produced.  The  elongating 
caulicle  is  known  as  the  hypocotyl 
("below  the  cotyledons").  That 
is,  the  hypocotyl  is  that  part  of  the 
stem  of  the  plant  let  lying  between 
the  roots  and  the  cotyledon.  The 
general  direction  of  the  young  hypocotyl  or  emerging 
caulicle  is  downwards.     As  soon  as  roots  form,  it  becomes 


311.  Cotyledons  of  germi- 
nating bean  spread  apart 
to  show  elongating  cauli- 
cle and  plumule. 


312.  Germination  of  bear 


174 


GERMINATION 


fixed,  and  its  subsequent  growth  tends  to  raise  the  cotyle- 
dons above  the  ground,  as  in  the  bean. 

339.  When  cotyledons  rise  into  the  air,  germination  is 
said  to  be  epigeal  ("above  the  earth").  Bean 
and  pumpkin  are  examples.  When  the  hypo- 
cotyl  does  not  elongate  greatly  and  the  coty-  313.  Sprouting  of 
ledons  remain  under  castorbean- 
ground,  the  germination  is  hypogeal  ("be- 
neath the  earth").  Pea  and  scarlet  run- 
ner bean  are  examples.  When  the  ger- 
minating seed  lies  on  a  hard  surface,  as 
on  closely  compacted  soil,  the  hypocotyl 
and  rootlets  may  not  be  able  to  secure  a 
<nK~^S^"  foothold    and    they    assume    grotesque 

— '       *  forms.     (Fig.  310.)     Try  this  with  peas 

314.  Germination  of  cas-  .    , 

tor  bean.    Endosperm      ailQ    DeanS. 

ata-  340.  The  first  inter- 

node  above  the  cotyledons — between  the 
cotyledons  and  the  plumule — is  the  epi- 
cotyl.  It  elevates  the  plumule  into  the  air, 
and  the  plumule-leaves  expand  into  the 
first  true  leaves  of  the  plant.  These  first 
true  leaves,  however,  may  be  very  unlike 
the  later  leaves. 

341.  Germination  of  Bean. —  The 
common  bean,  as  we  have  seen  (Fig. 
308),  has  cotyledons  that  occupy  all 
the  space  inside  the  seed-coats.  When 
the  hypocotyl  or  elongating  caulicle 
emerges,  the  plumule-leaves  have  begun 
to  enlarge  and  to  unfold.  (Fig.  311.)  The 
hypocotyl  elongates  rapidly.  One  end 
of  it  is  held  by  the  roots.  The  other  is 
held  by  the  seed-coats  in  the  soil.    It, 

Germination  complete      ,.  .  .  ,        ■;  c         ,  , 

in  castor  bean.  therefore,  takes  the  form  01  a  loop,  and 


315.  Castor  bean.  En- 
dosperm at  a,  a;  co- 
tyledons at  6. 


GERMINATION     IN     PARTICULAR    SEEDS 


175 


317.  Sprout- 
ing Indian 
corn.  Hi- 
lum  at  h; 

micropyle 
at  d. 


318.  Kernel  of 
Indian  corn. 
Caulicle  at 
6;  cotyledon 
a  ;  plumule 
P- 


its  central  part  "comes  up"  first,    (a,  Fig.  312.)    Presently 

it  draws  the  cotyledons  out  of  the  seed-coats,  and  then  it 

straightens  and  the  cotyledons  expand.  These  coty- 

fflT/j      ledons,  or  "halves  of  the  bean,"  persist  for  some 

Br!     time.    (6,  Fig.  312.)    They  often  become  green  and 

probably    perform     some    function    of 

foliage.    Because  of  its  large  size,  Lima 

bean  shows  all  these  parts  well. 

342.  Germination  of  Castor  Bean. 
— In  the  castor  bean  the  hilum  and 
micropyle  are  at  the  smaller  end.  (Fig. 
313.)  The  bean  "comes  up"  with  a 
loop,  which  indicates  that  the  hypocotyl 
greatly  elongates.  On  exam- 
ining a  germinating  seed,  however,  it  will  be 
found  that  the  cotyledons  are  contained  inside 
fleshy  body  or  sac.  (a,  Fig.  314.)  This 
sac  is  the  endosperm.  To  its  inner  sur- 
face the  thin,  veiny  cotyledons  are 
very  closely  appressed,  absorbing  its 
substance.  (Fig.  315.)  The  cotyledons 
increase  in  size  as  they  reach  the  air  (Fig.  316),  and  become 

functional  leaves. 

J  343.  Germination  of  Indian  Corn. — Soak  kernels  of 

I       corn.    Note  that  the  micropyle  and   hilum  are  at  the 

(I  ~  smaller  end.  (Fig.  317.)    Make  a  longi- 

A  [  tudinal   section   through    the   narrow 

^^^Jp^^:^      diameter;    Fig.    318    shows    it,     The 

Pi    l^ptf?w  single  cotyledon  is  at  a, 

the   caulicle   at   b,   the 

plumule    at    p.      The 

cotyledon    remains     in 

the   seed.     The  food  is 

stored  both  in  the  cotyledon  and  as  endosperm,  chiefly  the 

latter.   The  emerging  shoo,t  is  the  plumule,  with  a  sheathing 


319.   Indian  corn.    Cau- 
licle at  c;  roots  emerg- 
ing at  m;  plumule  at  p. 


Indian  corn.    o.   plumule; 
n  to  p,  epicotyl. 


176 


GERMINATION 


leaf,  (p,  Fig.  319.)  The  root  is  produced  from  the  tip  of  the 
caulicle,  c.  The  caulicle  is  held  in  a  sheath  (formed  mostly 
from  the  seed-coats),  and  some  of  the  roots  escape  through 
the  upper  end  of  this  sheath,  (m,  Fig.  319.)  The  epicotyl 
elongates,  particularly  if  the 
seed  is  planted  deep  or  if  it  is 
kept  for  some  time  confined. 
In  Fig.  320  the  epicotyl  has  elon- 
gated from  n  to  p.  The  true 
plumule-leaf  is  at  o,  but  other 
leaves  grow  from  its  sheath. 
In  Fig.  321  the  roots  are  seen 
emerging  from  the  two  ends  of 
the  caulicle-sheath,  c,  m;  the 
epicotyl  has  grown  to  p;  the 
first  plumule-leaf  is  at  o. 

Review. — What  does  a  seed  con- 
tain? What  do  you  understand  by 
the  embryo?  What  are  its  parts? 
Where  is  the  food  in  the  seed?  What 
are  the  seed-coats?  What  is  the  mi- 
cropyle?  Hilum?  How  may  the 
position  of  the  micropyle  be  deter- 
mined? How  do  seeds  differ?  With 
what  are  these  differences  associated? 
What  is  germination?  Under  what 
conditions  does  a  seed  germinate? 
What  is  meant  by  seed  vitality? 
What  are  the  best  conditions  for 
storage  of  seed?  When  is  germination 
complete?  What  is  the  first  phenom- 
enon of  germination?  Explain  the  relation  to  O  and  CO2.  Define 
hypocotyl.  Epicotyl.  Hypogeal  and  epigeal  germination.  What  be- 
comes of  the  plumule?  Explain  germination  in  a  seed  which  you 
have  studied. 

Note.— Few  subjects  connected  with  the  study  of  plant-life  are  so 
useful  in  schoolroom  demonstrations  as  germination.  The  pupil 
should  prepare  the  soil,  plant  the  seeds,  water  them  and  care  for  the 


321.  Germination  is  complete,  p,  top 
of  epicotyl;  o,  plumule-leaf;  m, 
roots;  c,  lower  roots. 


328 
Casting 
the  seed- 
323.  Natural  planting  of  the  fruits  of  Norway  maple.  coats. 


,    - 


327.    The  wing  cast  off;  the  329.   Free  from  the 

seed -coats  still  adhering.  seed-coats. 

(177) 


178  GERMINATION 

plants.  Plant  in  pots  or  shallow  boxes.  Cigar-boxes  are  excellent. 
The  depth  of  planting  should  be  two  to  three  times  the  diameter  of 
the  seeds.  It  is  well  to  begin  the  planting  of  seeds  at  least  ten  days 
in  advance  of  the  lesson,  and  to  make  four  or  five  different  plantings 
at  intervals.  A  day  or  two  before  the  study  is  taken 
up,  put  seeds  to  soak  in  moss  or  cloth.  The  pupil 
then  has  a  series  from  swollen  seeds  to  complete  ger- 
mination, and  all  the  steps  can  be  made  out.  Dry 
seeds  should  be  had  for  comparison. 

Good  seeds  for  study  are  those  detailed  in  the  les- 
son,— bean,  castor  bean,  corn.  Pea  is  a  good  plant  to 
contrast  with  bean.  (Fig.  322.)  Make  drawings  and 
notes  of  all  the  events  in  the  germination.  Note  the 
effects  of  unusual  conditions,  as  planting  too  deep  and 
too  shallow  and  different  sides  up.  For  hypogeal  ger- 
mination, use  the  garden  pea,  scarlet  runner  or  Dutch 
case-knife  bean,  acorn,  horse-chestnut.  Squash  seeds 
are  excellent  for  germination  studies,  because  the  coty- 
ledons become  green  and  leafy  and  germination  is  rapid. 
Its  germination,  as  also  that  of  the  scarlet  runner  bean, 
is  explained  in  "Lessons  with  Plants."  Onion  is  ex- 
cellent, except  that  it  germinates  too  slowly.  In  order 
to  study  the  root  development  of  germinating  plantlets,  it  is  well 
to  provide  a  deep  box  with  a  glass  side  against  which  the  seeds  are 
planted. 

Observe  the  germination  of  any  seed  that  is  common  about  the 
premises.  Where  elms  and  maples  are  abundant,  the  germination  of 
their  seeds  may  be  studied  in  lawns  and  along  fences.  Figs.  323  to 
330  suggest  observations  on  the  Norway  maple,  which  is  a  common 
ornamental  tree. 


CHAPTER  XXVI 

PHENOGAMS  AND   CRYPTOGAMS 

344.  The  plants  thus  far  studied  produce  flowers;  and 
the  flowers  produce  seeds  by  means  of  which  the  plant  is 
propagated.  There  are  other  plants,  however,  that  pro- 
duce no  seeds,  and  these  plants  are  probably  more  numerous 
than  the  seed-bearing  plants.  These  plants  propagate  by 
means  of  spores,  which  are  generative  cells,  usually  simple, 
containing  no  embryo.  These  spores  are  very  small,  and 
sometimes  are  not  visible  to  the  naked  eye. 

345.  Prominent  amongst  the  spore-propagated  plants 
are  ferns.  The  common  Christinas  fern  (so  called  because 
it  remains  green  during  winter)  is  shown  in  Fig.  331.  The 
plant  has  no  trunk.  The  leaves  spring  directly  from  the 
underground  stem.  The  leaves  of  ferns  are  called  fronds. 
They  vary  in  shape,  as  other  leaves 
do.  Compare  Fig.  139  and  the 
pictures  in  this  chapter.  Some  of 
the  fronds  are  seen  to  be  narrower 
at  the  top.  If  these  are  examined 
more  closely  (Fig.  332)  it  will  be 
seen  that  the  leaflets  are  contracted 
and  are  densely  covered  beneath 
with  brown  bodies.  These  bodies 
are  collections  of  sporangia  or  spore- 
cases  (singular,  sporangium). 

346.  The  sporangia  are  collected  into  little  groups, 
known  as  sort  (singular,  sorus)  or  fruit-dots.  Each  sorus  is 
covered  with  a  thin  scale  or  shield,  known  as  an  indusium. 
This  indusium  separates  from  the  frond  at  its  edges,  and  the 

(179) 


331.  Christmas  fern. — Dryopteris 
acrostichoides;  known  also  aa 
Aspidium. 


180 


PHENOGAMS    AND     CRYPTOGAMS 


332.  Fruiting  frond  of  Christ- 
mas fern.  Sori  at  a.  One 
sorus  with  its  indusium,  at  b. 


sporangia  are  exposed.  Not  all  ferns  have  indusia.  The 
polypode  (Figs.  333,  334)  does  not:  the  sori  are  naked.  In 
the  brake  (Fig.  335)  and  maiden- 
hair (Fig.  336)  the  edge  of  the  frond 
turns  over  and  forms  an  indusium. 
In  some  ferns  (Fig.  337)  an  entire 
frond  becomes  contracted  to  cover 
the  sporangia.  In  other  cases  the 
indusium  is  a  sac-like  covering, 
which  splits.    (Fig.  338.) 

347.  The  sporangium  or  spore- 
case  of  a  fern  is  a  more  or  less  globu- 
lar body  and  usually  with  a  stalk. 
(Fig.  334.)  It  contains  the  spores. 
When  ripe,  it  bursts  and  the  spores 
are  set  free.  Lay  a  mature  fruiting 
frond  of  any  fern  on  white  paper,  top  side  up,  and  allow  it 
to  remain  in  a  dry,  warm  place.  The  spores  will  discharge 
on  the  paper. 

348.  In  a  moist,  warm  place  the  spores  germinate.  They 
produce  a  small,  flat,  thin,  green,  more  or  less  heart-shaped 
membrane.    (Fig.  339.)    This  is  the  prothallus.    Sometimes 

the  prothallus  is  an  inch  or 
more  across,  but  oftener  it 
is  less  than  one-fourth  this 
size.   It  is  com- 
/   monly      un- 
known    except 
to  botanists. 
Prothalli   may 
often  be  found 
334.  Sori  and  sporan-  in   greenhouses 

gium  of  polypode.       where   ferng  ^ 

grown.    Look  on  the  moist  stone  or  brick  walls,  or  on  the 
firm  soil  of  undisturbed  pots  and  beds. 


333.  Common  polypode  fern. 
Polypodium  vulgare. 


PROTHALLUS  181 

349.  On  the  under  side  of  the  prothallus  two  kinds  of 
organs  are  borne.  These  are  the  archegonium  and  the  anthe- 
ridium.  These  organs  are  minute  specialized  parts  of  the 
prothallus.    Their  positions  on  a  particular  prothallus  are 

shown  at  a  and  b  in  Fig.  339,  but  in  some 
ferns  they  are  on  separate  prothalli  (plant 
dioecious).  The  sperm-cells  escape  from 
the  antheridium  and  in  the  water  which 

335.  The    brake    fruits  ,,       ,  ,,  .in  •     i    ^ 

underneath  the  revo-  collects  on  the   prothallus  are  carried  to 
lute  edges  of  the  leaf.  the  archegonium;  where  fertilization  takes 

place.  From  a  fertilized  archegonium  a  plant  grows,  and 
this  plant  becomes  the  "fern."  In  most  cases  the  prothallus 
dies  soon  after  the  fern  plant  begins  to  grow. 

350.  The  fern  plant,  arising  from  the  fertilized  egg  in  the 
archegonium,  becomes  a  perennial  plant,  each  year  pro- 
ducing spores  from  its  fronds,  as  we  have  seen;  but  these 
spores — which  are  merely  detached  special  kinds  of  cells — 
produce  the  prothallic  phase  of  the  fern  plant,  from  which 
new  individuals  arise.  A  fern  is  fertilized  but  once  in  its 
life-time.  The  prothallium  here  is  the  gametophyte;  the  "fern" 
is  the  sporophyte  (phyton  is  Greek  for  "plant"). 

351.  This  succession 
of  generations  runs  all 
through  the  vegetable 
kingdom,  although  there 
are  some  groups  of  plants 
in  which  it  is  very  ob- 
scure or  apparently  want- 
ing. It  is  very  marked 
in  ferns  and  mosses.    In 

1~„.    /•„„!, .J: j.U« „  336.  Reflexed  margins  of  a  maidenhair  frond. 

algce  (including  the  sea- 
weeds) the  gametophyte  constitutes  the  "plant,"  as  the  non- 
botanist  knows  it.    There  is  a  general  tendency,  in  the  evo- 
lution of  the  vegetable  kingdom,  for  the  gametophyte  to  lose 
its  relative  importance  and  for  the  sporophyte  to  become 


182 


PHENOGAMS    AND    CRYPTOGAMS 


337.  Fertile  and  sterile  fronds 
of  the  sensitive  fern. 


larger  and  more  highly  developed.  In  the  seed-bearing 
plants  the  sporophyte  generation  is  the  only  one  seen  by  the 
non-botanist.  The  gametophyte 
stage  is  of  short  duration  and  the 
parts  are  small:  it  is  confined  to  the 
time  of  fertilization. 

352.  The  sporophyte  of  the  seed- 
plants,  or  the  plant,  as  we  know  it, 
produces  spores  which,  however,  are 
not  visible  to  the  naked  eye.  The 
spores  are  of  two  kinds:  microspores 
borne  in  tissues  called  sporangia 
which  forms  part  of  the  anther;  and 
macrospores  which 
are  present  in  the 
pistil.  The  microspore  developes  into  the 
pollen-grain.  The  macrospore  develops 
in  the  ovule  into  an  embryo-sac,  which 
contains  the  egg  nucleus.  The  germi- 
nated pollen-grain  constitutes  the  com- 
pletely developed  sterile  gametophyte. 
The  fully  developed  embryo-sac  constitutes  the  fertile  gam- 
etophyte. Fertilization  occurs,  and  the  sporophyte  is  again 
produced.  This  new  sporophyte 
develops  farther  and  we  have  the 
embryo  plant  formed  in  the  seed. 
This  may  remain  dormant  for  a 
time,  and  when  germination 
occurs  the  visible  sporophyte  plant 
is  produced.  This  in  turn  produces 
microspores  and  macrospores,  and 
the  cycle  is  again  complete.  The 
alternation  of  these  phases  in  the 
plant's  life  history  is  known  technically  as  alternation  of 
generations. 


338.  A  sac-like  indusium. 


339.  Prothallus  of  a  fern.  Enlarged. 
Archegonia  at  a;  antheridia  at  b. 


THE     TWO     GREAT    CLASSES     OF     PLANTS  183 

353.  It  happens  that  the  spores  of  seed-bearing  plants 
are  borne  amongst  a  mass  of  specially  developed  leaves 
known  as  flowers:  therefore,  these  plants  have  been  known 
as  the  flowering  plants.  Some  of  the  leaves  are  developed  as 
envelopes  (calyx,  corolla),  and  others  as  spore-bearing 
parts,  or  sporophylls  (stamens,  pistils).  But  the  spores  of 
the  lower  plants,  as  of  ferns  and  mosses,  may  also  be  borne 
in  specially  developed  foliage,  so  that  the  line  of  demar- 
cation between  flowering  plants  and  flowerless  plants  is  not 
so  definite  as  was  once  supposed.  The  one  definite  dis- 
tinction between  these  two  classes  of  plants  is  the  fact  that 
one  class  produces  seeds  and  the  other  does  not.  The  seed- 
plants  are  now  often  called  spermaphytes,  but  there  is  no 
single  coordinate  term  to  set  off  those  which  do  not  bear 
seeds.  It  is  quite  as  well,  for  popular  purposes,  to  use  the  old 
terms,  phenogams  for  the  seed-bearing  plants  and  cryptogams 
for  the  others.  These  terms  have  been  objected  to  in  recent 
years  because  their  etymology  does  not  express  literal  facts 
(phenogam  refers  to  the  fact  that  the  flowers  are  showy,  and 
cryptogam  to  the  fact  that  the  parts  are  hidden),  but  the 
terms  represent  distinct  ideas  in  classification.  Nearly 
every  word  in  the  language  has  grown  away  from  its  ety- 
mology. The  cryptogams  include  three  great  series  of 
plants — the  Thallophytes  or  algae,  lichens  and  fungi;  the 
Bryophytes  or  moss-like  plants;  the  Pteridophytes  or  fern- 
like plants.  In  each  of  these  series  there  are  many  families. 
See  the  following  Chapter. 

Review. — What  is  a  spore?  Describe  the  appearance  of  some 
fern  plant  that  you  have  studied.  What  are  the  spores  and  sporangia? 
What  is  a  sorus?  Indusium?  What  grows  from  the  spore?  How  does 
the  new  "fern"  plant  arise?  What  is  meant  by  the  ph  ase  "alternation 
of  generations?"  Define  gametophyte  and  sporophyte.  Describe 
the  alternation  in  flowering  plants.  Explain  the  flower  from  this  point 
of  view.  What  is  the  significance  of  the  word  spermaphyte?  Contrast 
phenogam  and  cryptogam. 

Note. — All  the  details  of  fertilization  and  of  the  development  of 


184  PHENOGAMS    AND    CRYPTOGAMS 

the  generations  are  omitted  from  this  book,  because  they  are  subjects 
for  specialists  and  demand  more  training  in  research  methods  than 
the  high-school  pupil  can  properly  give  to  plant-study.  Cryptogams 
are  as  widespread  as  phenogams,  and  for  this  reason  it  has  been 
urged  that  they  are  most  proper  subjects  for  study  in  the  school.  This 
position  is  untenable,  however,  for  the  best  plant  subjects  for  youth 
are  those  which  mean  most  to  his  life.  It  is  said,  also,  that  cryptogams 
are  best  for  the  beginner  because  their  life-processes  are  relatively 
simple  in  many  cases;  but  the  initial  study  of  plants  should  be  under- 
taken for  the  purpose  of  quickening  the  pupil's  perception  of  common 
and  familiar  forms  and  problems,  rather  than  for  the  purpose  of  de- 
veloping a  technical  knowledge  of  a  given  science. 


CHAPTER  XXVII 

STUDIES   IN   CRYPTOGAMS 

The  special  advanced  pupil  who  has  acquired  skill  in 
the  use  of  the  compound  microscope  may  desire  to  make 
more  extended  excursions  into  the  cryptogamous  orders. 
The  following  plants,  selected  as  examples  in  various  groups, 
will  serve  as  a  beginning. 

AIXLE 

The  algae  comprise  most  of  the  green  floating  "scum"  which  covers 
the  surface  of  ponds  and  other  quiet  waters.  The  masses  of  plants 
are  often  called  "frog  spittle."  Others  are  attached  to  stones,  pieces 
of  wood  and  other  objects  submerged  in  streams  and  lakes,  and  many- 
are  found  on  moist  ground  and  on  dripping  rocks.  Aside 
from  these,  all  the  plants  commonly  known  as  seaweeds 
belong  to  this  category.  They  are  inhabitants  of  salt  water. 

The  simplest  forms  of  alga;  consist  of  a  single  spherical 
cell,  which  multiplies  by  repeated  division  or  fission. 
Specimens  of  these  may  be  found  growing  on  damp  rock 
and  the  shady  side  of  trees.  Most  of  the  forms  found  in 
fresh  water  are  filamentous,  i.e.,  the  plant-body  consists 
of  long  threads,  either  simple  or  branched.  Such  a  plant- 
body  is  termed  a  thnlhis.  This  term  applies  to  the  vege- 
tative body  of  all  plants  which  are  not  differentiated  into 
stem  and  leaves.  Such  plants  are  known  as  thallophytes 
(353).  All  alga?  contain  chlorophyll,  and  are  able  to  as- 
similate carbon  dioxid  from  the  air.  This  distinguishes 
them  from  the  fungi. 

Spirogyra. — One  of  the  most  common  forms  of  the 
green  algse  is  spirogyra.  (Fig.  340.)  This  plant  frequently 
forms  the  greater  part  of  the  floating  green  mass  on  ponds. 
The  filamentous  character  of  the  thallus  can  be  seen  with 
the   naked    eye   or   with    a    hand    lens,    but    to    study   it    carefully 


^a 


340.  Strund  of 
spirogyra, 
showing 
the  chloro- 
phyll bands. 
There  is  a 
nucleus  at  o. 


a   microscope  magnifying    two 


hundred 

ri85) 


diameters   or  more   should 


186 


STUDIES    IN    CRYPTOGAMS 


be  used.  The  thread  is  divided  into  long  cells  by  cross-walls  which, 
according  to  the  species,  are  either  straight  or  curiously  folded.  (Fig. 
341.)  The  chlorophyll  is  arranged  in  beautiful  spiral  bands  near  the 
wall  of  each  cell.  From  the  character  of  these  bands  the  plant  takes 
its  name.  Each  cell  is  provided  with  a  nucleus  and  other 
protoplasm.  The  nucleus  is  suspended  near  the  center 
of  the  cell,  a,  Fig.  340,  by  delicate  strands  of  proto- 
plasm radiating  toward  the  wall  and  terminating  at 
certain  points  in  the  chlorophyll  band.  The  remainder 
of  the  protoplasm  forms  a  thin  layer  lining  the  wall. 
The  interior  of  the  cell  is  filled  with  cell-sap.  The  pro- 
toplasm and  nucleus  cannot  be  easily  seen,  but  if  the 
plant  is  stained  with  a  dilute  alcoholic  solution  of  eosin 
(153)  they  become  clear. 

Spirogyra  is  propagated  vegetatively  by  the  break- 
ing off  of  parts  of  the  threads,  which  continue  to  grow 
as  new  plants.  Resting-spores,  which  may  remain  dor- 
mant for  a  time,  are  formed  by  a  process  known  as  con- 
jugation. Two  threads  lying  side  by  side  send  out 
short  projections,  usually  from  all  the  cells  of  a  long 
series.  (Fig.  341.)  The  projections  or  processes  from 
opposite  cells  grow  toward  each  other,  meet  and  fuse, 
forming  a  connecting  tube  between  the  cells.  The 
protoplasm,  nucleus  and  chlorophyll  band  of  one  cell 
now  pass  through  this  tube,  and  unite  with  the  con- 
tents of  the  other  cell.  The  entire  mass  then  becomes  surrounded  by 
a  thick  cellulose  wall,  thus  completing  the  resting-spore,  or  zygospore. 
(Fig.  341,  z.) 

Vaucheria  is  another  alga  common  in  shallow  water  and  on  damp 
soil.  The  thallus  is  much  branched,  but  the  threads  are  not  divided 
by  cross-walls  as  in  spirogyra.  The  plants  are  attached  by  means  of 
colorless  root-like  organs  which  are  much  like  the  root-hairs  of  the 
higher  plants:  these  are  rhizoids.  The  chlorophyll  is  in  the  form  of 
grains  scattered  through  the  thread. 

Vaucheria  has  a  special  mode  of  vegetative  reproduction  by  means 
of  swimming  spores  or  swarm-spores.  These  are  formed  singly  in  a 
6hort,  enlarged  lateral  branch  known  as  the  sporangium.  When  the 
sporangium  bursts  the  entire  contents  escape,  forming  a  single  large 
swarm-spore,  which  swims  about  by  means  of  numerous  lashes  or  cilia 
on  its  surface.  The  swarm-spores  are  so  large  that  they  can  be  seen  with 
the  naked  eye.  After  swimming  about  for  some  time  they  come  to 
rest  and  germinate,  producing  a  new  plant, 


341.  Conjugation 
of  spirogyra. 
Ripe  zygo- 
spores on  the 
left ;  connect- 
ing a,  tubes. 


ALG^-FUNGI 


187 


The  formation  of  resting-spores  of  vaucheria  is  accomplished 
by  means  of  special  organs,  oogonia  Fig.  342.  o,  and  antheridia.  (Fig. 
342,  a.)  Both  of  these  are  specially  developed  branches  from  the  thallus. 
The  antheridia  are  nearly  cylin- 
drical, and  curved  toward  the 
oogonia.  The  upper  part  of  an 
antheridium  is  cut  off  by  a 
cross-wall,  and  within  it  nu- 
merous ciliated  sperm-cells  are 
formed.  These  escape  by  the 
ruptured  apex  of  the  antherid- 
iiun.  The  oogonia  are  more  enlarged  than  the  antheridia  and  have 
a  beak-like  projection  turned  a  little  to  one  side  of  the 
apex.  They  are  separated  from  the  thallus-thread  by  a 
cross-wall,  and  contain  a  single  large  green  cell,  the  egg- 
cell.  The  apex  of  the  oogonium  is  dissolved,  and  through 
the  opening  the  sperm-cells  enter.  Fertilization  is  thus 
accomplished.  After  fertilization,  the  egg-cell  becomes 
invested  with  a  thick  wall  and  is  thus  converted  into  a 
of  "vaucheria!    resting-spore,  the  oospore.    (Fig.  343.) 


342.  Thread  of  vaucheria  with  oogonia 
and  antheridia. 


FUNGI 


Some  forms  of  fungi  are  familiar  to  every  one.  Mushrooms  and 
toadstools,  with  their  varied  forms  and  colors,  are  common  in  fields, 
woods  and  pastures.  In  every  household  the  common  moulds  are 
familiar  intruders,  appearing  on  old  bread,  vegetables  and  even  within 
tightly  sealed  fruit  jars,  where  they  form  a  felt-like  layer  dusted  over 
with  blue,  yellow  or  black  powder  (192).  The 
strange  occurrence  of  these  plants  long  mystified 
people,  who  thought  they  were  productions  of  the 
dead  matter  upon  which  they  grew,  but  now  we 
know  that  a  mould,  like  any  other  plant,  cannot 
originate  spontaneously;  it  must  start  from  some- 
thing which  is  analogous  to  a  seed.  The  "seed" 
in  this  case  is  a  spore.  The  term  spore  is  applied 
to  the  minute  reproductive  bodies  of  all  flower- 
less  plants.  A  spore  is  a  very  simple  structure, 
usually  of  only  one  plant-cell,  whose  special 
function  is  to  reproduce  the  plant.  A  spore  may 
be  produced  by  a  vegetative  process  (growing  out  from  the  ordinary 
plant  tissues),  or  it  may  be  the  result  of  a  fertilization  process  (.'if  f  I. 


344.    Mucor   muredc 
showing  habit. 


188 


STUDIES    IN    CRYPTOGAMS 


345.  Spores  of  mucor; 
some  germinating. 


Mould. — One  of  these  moulds,  Mucor  mucedo,  which  is  very  com- 
mon on  all  decaying  fruits  and  vegetables,  is  shown  in  Fig.  344,  some- 
what magnified.  When  fruiting,  this  mould  appears  as  a  dense  mass 
of  long  white  hairs,  often  over  an  inch  high,  standing  erect  from  the 
fruit  or  vegetable  upon  which  it  is  growing. 

The  life  of  this  mucor  begins  with  a  minute 
rounded  spore  (a,  Fig.  345),  which  lodges  on  the 
decaying  material.  When  the  spore  germinates,  it 
sends  out  a  delicate  thread  which  grows  rapidly  in 
length  and  forms  very  many  branches  which  soon 
permeate  every  part  of  the  substance  on  which  the 
plant  grows,  (b,  Fig.  345.)  One  of  these  threads  is  termed  a  hypha.  All 
the  threads  together  from  the  mycelium  of  the  fungus  (194).  The 
mycelium  disorganizes  the  material  in  which  it  grows,  and  thus  nour- 
ishes the  mucor  plant.  (Fig.  344.)  It  corresponds  physiologically  to  the 
roots  and  stems  of  other  plants. 

When  the  mycelium  is  about  two  days  old,  it  begins  to  form  the 
long  fruiting  stalks  which  we  first  noticed.  To  study  them,  use  a 
compound  microscope  magnifying  about  two  hundred  diameters.  One 
of  the  stalks,  magnified,  is  shown  in  Fig.  346,  a.  It  consists  of  a  rounded 
head,  the  sporangium,  sp,  supported  on  a  long,  delicate  stalk,  the 
sporangiophore,  st.  The  stalk  is  separated  from  the  sporangium  by 
a  wall  which  is  formed  at  the  base  of  the  sporangium.  This  wall,  how- 
ever, does  not  extend  straight  across  the 
thread,  but  it  arches  up  into  the  sporangium 
like  an  inverted  pear.  It  is  known  as  the 
columella,  c.  When  the  sporangium  is  placed 
in  water,  the  wall  immediately  ruptures  and 
allows  hundred  of  spores,  which  were  formed 
in  the  cavity  within  the  sporangium,  to 
escape,  b.  All  that  is  left  of  the  fruit  is 
the  stalk,  with  the  pear-shaped  columella 
at  its  summit,  c.  The  spores  which  have  been 
set  free  by  the  breaking  of  the  sporangium 
wall  are  now  scattered  by  the  wind  and 
other  agents. .  Those  which  lodge  in  favor- 
able places  begin  to  grow  immediately  and 
reproduce  the  fungus.  The  others  soon  perish . 
The  mucor  may  continue  to  reproduce  itself  in  this  way  indefi- 
nitely, but  these  spores  are  very  delicate  and  usually  die  if  they  do  not 
fall  on  favorable  ground,  so  that  the  fungus  is  provided  with  another 
means  of  carrying  itself  over  unfavorable  seasons,  as  winter.    This  is 


ucor.  a,  sporangium; 
b,  sporangium  bursting; 
s,  columella. 


FUNGI 


189 


t° 


accomplished  by  means  of  curious  thick-walled  resting-spores  or  zygo- 
spores. The  zygospores  are  formed  on  the  mycelium  buried  within 
the  substance  on  which  the  plant,  grows.  They  originate  as  follows 
The  threads  of  two  sexually  different  plants  that 
lie  near  together  send  out  short  branches,  which 
grow  toward  each  other  and  finally  meet.  (Fig.  347.) 
The  walls  at  the  ends,  a,  then  disappear,  allowing 
the  contents  to  flow  together.  At  the  same  time, 
however,  two  other  walls  are  formed  at  points 
farther  back,  b,  b,  separating  the  short  section,  c, 
from  the  remainder  of  the  thread.  This  section  now 
increases  in  size  and  becomes  covered  with  a  thick, 
dark  brown  wall  ornamented  with  thickened  tu- 
bercles. The  zygospore  is  now  mature  and,  after 
a  period  of  rest,  it  germinates,  either  producing  a 
sporangium  directly  or  growing  out  as  mycelium. 

The  zygospores  of  the  mucors  form  one  of  the 
most  interesting  and  instructive  objects  among  the 
lower  plants.  They  are,  however,  very  difficult  to 
obtain.  One  of  the  mucors,  Sporodinia  grandis, 
may  be  frequently  found  in  summer  growing  on 
toadstools.  This  plant  usually  produces  zygospores, 
which  are  formed  on  the  aerial  mycelium.  The 
zygospores  are  large  enough  to  be  recognized  with  a  hand  lens.  The 
material  may  be  dried  and  kept  for  winter  study,  or  the  zygospores  may 
be  prepared  for  permanent  microscopic  mounts  in  the  ordinary  way. 

Willow  mildew. — Most  of  the  molds  are  saprophytes  (192).  There 
are  many  other  fungi  which  are  parasitic  on  living  plants  and  animals. 
Some  of  them  have  interesting  and  complicated  life-histories,  under- 
going many  changes  before  the  original  spore  is  again  produced.    The 

willow  mildew  and  the 
common  rust  of  wheat 
will  serve  to  illustrate  the 
habits  of  parasitic  fungi. 
The  willow  mildew 
(Uncinula  salicis)  forms 
white  downy  patches  on 
the  leaves  of  willows.  (Fig.  348.)  These  patches  consist  of  numer- 
ous interwoven  threads  which  may  be  recognized  as  the  mycelium 
of  the  fungus.  The  mycelium  in  this  case  lives  on  the  surface  of  the 
leaf  and  nourishes  itself  by  sending  short  branches  into  the  cells  of  the 
leaf  to  absorb  food-materials  from  them. 


347.  Muoor  showing 
formation  of  zygo- 
spore on  the  right; 
germinating  zygo- 
spore on  the  left. 


348.  Colonies  of  willow  mildew. 


190 


STUDIES    IN     CRYPTOGAMS 


349.  Summer-spores  of  willow 
mildew. 


Numerous  summer-spores  are  formed  on  short  erect  branches  all 
over  the  white  surface.  One  of  these  branches  is  shown  in  Fig.  349. 
When  it  has  grown  to  a  certain  length,  the  upper  part  begins  to  segment 
or  divide  into  spores  which  fall  and  are  scattered  by  the  wind.  Those 
falling  on  other  willows  reproduce  the 
fungus  there. 

This  process  continues  all  summer, 
but  in  the  later  part  of  the  season  pro- 
vision is  made  to  maintain  the  mildew 
through  the  winter.  If  some  of  the  white 
patches  are  closely  examined  in  July  or 
August,  a  number  of  little  black  bodies 
will  be  seen  among  the  threads.  These 
little  bodies,  called  perithecia,  are  shown  in 
Fig.  350.  To  the  naked  eye  they  appear 
as  minute  specks,  but  when  seen  under  a  magnification  of  200  diameters 
they  present  a  very  interesting  appearance.  They  are  hollow  spheri- 
cal bodies  decorated  around  the  outside  with  a  fringe  of  crook-like 
hairs.  The  resting-spores  of  the 
willow  mildew  are  produced  in 
sacs  or  asci  inclosed  within  the 
leathery  perithecia.  Fig.  351 
shows  a  cross-section  of  a  peri- 
thecium  with  the  asci  arising 
from  the  bottom.  The  spores 
remain  securely  packed  in  the 
perithecia.  They  do  not  ripen  in 
the  autumn  but  fall  to  the 
ground  with  the  leaf  and  there 
remain  securely  protected  among 
the  dead  foliage.  The  following 
spring  they  mature  and  are  lib- 
erated by  the  decay  of  the  peri- 
thecia. They  are  then  ready  to  attack  the  unfolding  leaves  of  the 
willow  and  repeat  the  work  of  the  summer  before. 

Wheat  rust. — The  development  of  some  of  the 
rusts,  like  the  common  wheat  rust  (Puccinia  gram- 
inis),  is  even  more  interesting  and  complicated 
than  that  of  the  mildews.  Wheat  rust  is  also  a  true 
parasite,  affecting  wheat  and  a  few  other  grasses. 
351.  Section  through    The  myceliUm  here  cannot  be  seen  by  the  unaided 

penthecium  of   wil-  „        .,  .,         „,.  ,  ,., 

low  mildew,  eye,  for  it  consists  of  threads  which  are  present 


350.  Perithecium    of  willow  mildew. 


FUNGI 


191 


352., 

Sori  containing  teleu- 
tospores  of  wheat 
rust. 


within  the  host -plant,  mostly  in  the  intercellular  spaces.  These 
threads  also  send  short  branches,  or  haustoria  (194),  into  the  neighbor- 
ing cells  to  absorb  nutriment. 

The  resting-spores  of  wheat  rust  are 
produced  in  late  summer,  when  they  may 
be  found  in  black  lines  breaking  through  the 
epidermis  of  the  wheat-stalk.  They  are 
formed  in  masses,  called  sori  (Fig.  3.52), 
from  the  ends  of  numerous  crowded  mycelial 
strands  just  beneath  the  epidermis  of  the 
host.  The  individual  spores  are  very  small 
and  can  be  well  studied  only  with  high 
powers  of  the  microscope  (x  about  400). 
They  are  brown  two-celled  bodies  with  a 
thick  wall.  (Fig.  353.)  Since  they  are  the 
resting-  or  winter-spores,  they  are  termed 
telcutospores  ("completed  spores")-  They 
usually  do  not  fall,  but  remain  in  the  sori 
during  winter.  The  following  spring  each 
cell  of  the  teleutospore  puts  forth  a  rather  stout  thread,  which  does 
not  grow  more  than  several  times  the  length  of  the  spore  and  termi- 
nates in  a  blunt  extremity.  (Fig.  354.)  This  germ-tube,  promycelium, 
now  becomes  divided  into  four  cells  by  cross-walls,  which  are  formed 
from  the  top  downwards.  Each  cell  gives  rise  to  a  short, 
pointed  branch  which,  in  the  course  of  a  few  hours,  forms  a 
single  small  spore  at  its  summit.  In  Fig.  354  a  germinating 
spore  is  drawn  to  show  the  basidium,  b,  divided  into  four 
cells,  each  producing  a  short  branch  with  a  little  sporidium,  s. 
A  most  remarkable  circumstance  in  the  life-history  of 
the  wheat  rust  is  the  fact  that  the  mycelium  produced  by 
the  teleutospore  can  live  only  in  barberry 
leaves,  and  it  follows  that  if  no  barberry 
bushes  are  in  the  neighborhood  the  sporidia 
finally  perish.  Those  which  happen  to  lodge  on 
a  barberry  bush  germinate  immediately,  pro- 
ducing a  mycelium  which  enters  the  barberry 
leaf  and  grows  within  its  tissues.  Wry  soon 
the  fungus  produces  a  new  kind  of  spores  on 
the  barberry  leaves.  These  are  called  ;ici<li<>- 
spores.  They  are  formed  in  long  chains  in  little  fringed  cups,  or  xcidia, 
which  appear  in  groups  on  the  lower  side  of  the  leaf.  (Fig.  355.)  These 
orange  or  yellow  aecidia  are  termed  cluster-cups.    In  Fig.  356  is  shown 


354.  Germi- 
nating  te- 
353.  leutospore 

Teuleutospore     of    wheat 

of  wheat  rust.      rust. 


192 


STUDIES     IN     CRYPTOGAMS 


355.  Leaf  of  barberry  with 
cluster-cups. 


a  cross-section  of  one  of  the  cups,  outlining  the  long  chains  of  spores, 
and  the  mycelium  in  the  tissues. 

The  aecidiospores  are  formed  in  the  spring,  and  after  they  have  been 
set  free  some  of  them  lodge  on  wheat  or  other  grasses,  where  they  germi- 
nate immediately.  The  germ-tube 
enters  the  leaf  through  a  stomate, 
whence  it  spreads  among  the  cells  of 
the  wheat  plant.  The  aecidiospores 
are  not  able  to  infect  the  barberry 
leaf.  During  summer  one-celled 
uredospores  ("blight  spores")  are 
produced  in  a  manner  similar  to  the 
teleutospores.  The  sori  bearing  them  are  red,  due  to  the  color  of  the 
spores  of  the  mass.  These  are  capable  of  germinating  immediately 
and  serve  to  disseminate  the  fungus  during  the  summer  on  other  wheat 
plants  or  grasses.  (Fig.  357.)  Late  in  the  season,  teleutospores  are  again 
produced,  completing  the  life  cycle  of  the  plant. 

Many  rusts  besides  Puccinia  graminis  produce  different  spore-forms 
on  different  plants.  The  phenom- 
enon is  called  heteroecism,  and 
was  first  shown  to  exist  in  the 
wheat  rust.  Curiously  enough,  the 
peasants  of  Europe  had  observed 
and  asserted  that  barberry  bushes 
cause  wheat  to  blight  long  before 
science  explained  the  relation  be- 
tween the  cluster-cups  on  barberry 
and  the  rust  on  wheat.  The  true 
relation  was  actually  demonstrated, 
as  has  since  been  done  for  many 
other  rusts  on  their  respective 
hosts,  by  sowing  the  aecidiospores 
on  healthy  wheat 
plants  and  thus  pro- 
ducing the  rust.  The 
cedar  apple  is  another 

rust,  the  fungus  producing  the  curious  swellings  often 
found  on  the  branches  of  red  cedar  trees.  In  the  spring 
the  teleutospores  ooze  out  from  the  "apple"  in  brownish  yellow  masses. 
It  has  been  found  that  these  attack  various  pomaceous  fruit  trees  pro- 
ducing fficidia  on  their  leaves.  Cedar  t/ees  about  orchards  may  be  a 
menace  unless  carefully  watched. 


356.  Section  through  a  cluster-cup  on 
barberry  leaf. 


LICHENS    AND    HEPATICS  193 


LICHENS 


Lichens  are  so  common  everywhere  that  the  attention  of  the  student 
is  sure  to  be  drawn  to  them.  They  grow  on  rocks  (Fig.  373),  trunks 
of  trees,  old  fences  and  on  the  earth.  They  are  too  difficult  for  begin- 
ners, but  a  few  words  of  explanation  may  be  useful. 

Lichens  were  formerly  supposed  to  be  a  distinct  or  separate  divi- 
sion of  plants.  They  are  now  known  to  be  organisms,  each  species  of 
which  is  a  constant  association  of  a  fungus  and  an  alga.  The  thallus 
is  ordinarily  made  up  of  fungous  mycelium  or  tissue,  within  which  the 
imprisoned  alga  is  definitely  distributed.  This  association  of  alga  and 
fungus  is  usually  spoken  of  as  symbiosis,  or  mutually  helpful  growth, 
both  together  being  able  to  accomplish  work  which  neither  could  do 
independently.  By  others  this  union  is  considered  to  be  a  mild  form 
of  parasitism,  in  which  the  fungus  profits  at  the  expense  of  the  alga. 
Each  component  may  be  able  to  grow  independently,  and  under  such 
conditions  the  algal  cells  seem  to  thrive  better  than  when  imprisoned 
by  the  fungus. 

Lichens  propagate  by  means  of  soredia,  which  are  tiny  parts  sepa- 
rated from  the  body  of  the  thallus,  and  consisting  of  one  or  more  algal 
cells  overgrown  with  fungous  threads.  These  are  readily  observed 
in  many  lichens.  They  also  produce  spores,  usually  ascospores,  which 
are  always  the  product  of  the  fungous  element,  and  which  reproduce  the 
lichen  by  germinating  in  the  presence  of  algal  cells,  to  which  the  hypha> 
immediately  cling. 

Lichens  are  found  in  the  most  inhospitable  places  and,  by  means 
of  acids  'which  they  secrete,  they  attack  and  slowly  disintegrate  even 
the  hardest  rocks.  By  making  thin  sections  of  the  thallus  with  a  sharp 
razor  and  examining  under  the  compound  microscope,  it  is  easy  to 
distinguish  the  two  components  in  many  lichens. 


LIVERWORTS 

The  liverworts  are  peculiar,  flat,  green  plants  usually  found  grow- 
ing on  wet  cliffs  and  in  other  moist,  shady  places.  They  frequently 
occur  in  greenhouses  where  the  soil  is  kept  constantly  wet.  One  of 
the  commonest  liverworts  is  Marchantia  polymorpha,  two  plants  of 
which  are  shown  in  Figs.  358,  359.  The  plant  consists  of  a  flat  ribbon- 
like thallus  which  spreads  over  the  soil,  becoming  repeatedly  forked 
as  it  grows.  The  end  of  each  branch  is  always  conspicuously  notched. 
There  is  a  prominent  midrib  extending  along  the  center  of  each  branch 


194 


STUDIES    IN     CRYPTOGAMS 


of  the  thallus.  On  the  under  side  of  the  thallus,  especially  along  the 
midrib,  there  are  numerous  rhizoids  which  serve  the  purpose  of  roots, 
absorbing  nourishment  from  the  earth  and  holding  the  plant  in  its 
place.  The  upper  surface  of  the  thallus  is  divided  into  minute  rhombic 
areas  which  can  be  seen  with  the  naked  eye.  Each  of  these  areas  is 
perforated  by  a  small  breathing  pore  or  stomate  which  leads  into  a 


358. 


Plants  of  marchantia 


cavity  just  beneath  the  epidermis.  This  space  is  surrounded  by  chloro- 
phyll-bearing cells,  some  of  which  stand  in  rows  from  the  bottom  of 
the  cavity.  (Fig.  360.)  The  delicate  assimilating  tissue  is  thus  brought 
in  close  communication  with  the  outer  air  through  the  pore  in  the 
thick  protecting  epidermis. 

At  various  points  on  the  midrib  are  little  cups  which  contain  small 
green  bodies.  These  bodies  are  buds  or  gemmae  which  are  outgrowths 
from  the  cells  at  the  bottom  of  the  cup.  They  become  loosened  and 
are  then  dispersed  by  the  rain  to  other  places  where  they  take  root  and 
grow  into  new  plants. 

The  most  striking  organs  on  the 
thallus  of  marchantia  are  the  pecu- 
liar stalked  bodies  shown  in  Figs.  358, 
359.  These  are  termed  archegonio- 
phore  and  antheridiophores  or  re- 
ceptacles, each  produced  on  separate 
plants.  Their  structure  and'  function 
are  very  interesting,  but  their  parts 
are  so  minute  that  they  can  be 
studied  only  with  the  aid  of  a  micro- 
scope magnifying  from  100  to  400  times.  Enlarged  drawings  will 
guide  the  pupil. 

The  antheridiophores  are  fleshy  lobed  disks  borne  on  short  stalks. 


360.  Section  of  thallus  of  marchantia. 
Stomate  at  a. 


LIVERWORTS 


195 


(Fig.  358.)  The  upper  surface  of  the  disk  shows  openings  scarcely- 
visible  to  the  naked  eye.  However,  a  section  of  the  disk,  such  as  is 
drawn  in  Fig.  361,  shows  that  the  pores  lead  into  oblong  cavities  in 
the  receptacle.  From  the  base  of  each  cavity  there  arises  a  thick 
club-shaped    body,    the    antheridium.     Within    the   antheridium    are 


361.  Section  through  antheridiophore  of  marehantia,  showing  antheridia. 
One  antheridium  more  magnified. 

formed  many  sperm-cells  which  are  capable  of  swimming  about  in 
water  by  means  of  long  lashes  or  cilia  attached  to  them.  When  the 
antheridium  is  mature,  its  wall  ruptures  and  allows  the  ciliated  sperm- 
cells  to  escape. 

The  archegoniophores  are  also  elevated  on  stalks.  (Fig.  359.)  In- 
stead of  a  simple  disk,  the  receptacle  consists  of  nine  or  more  finger- 
like rays.  Along  the  under  side  of  the  rays,  between  delicately  fringed 
curtains,  peculiar  flask-like  bodies,  or  archegonia,  are  situated.  The 
archegonia  are  not  visible  to  the  naked  eye.  They  can  be  studied  only 
with  the  microscope  (x  about  400).  One  of  them  much  magnified  is 
represented  in  Fig.  362.  Its  principal  parts  are  the  long  neck,  a,  and 
the  rounded  center,  b,  inclosing  a  large  free  cell — the  egg-cell. 

We  have  seen  that  the  antheridium  at  maturity  discharges  its 
sperm-cells.  These  swim  about  in  the  water  provided 
by  the  dew  and  rain.  Some  of  them  finally  find  their 
way  to  the  archegonia  and  egg-cells,  which  are  thus 
fertilized,  as  pollen  fertilizes  the  ovules  of  higher  plants. 

After  fertilization  the  egg-cell 
develops  into  the  spore-capsule  or 
sporogonium.  The  mature  spore- 
capsules  may  be  seen  in  Fig.  363. 
They  consist  of  an  oval  spore-case 
on  a  short  stalk,  the  base  of  which 
is  imbedded  in  the  tissue  of  the  re- 
ceptacle from  which  it  derives  the 
necessary  nourishment  for  the  de-  363.  Archegoniophore 
.  ..         W1,h  sP'Togoma  of 

veloprnent  of  the  sporogonium.    At       marehantia. 


196 


STUDIES     IN     CRYPTOGAMS 


364.  Spores  and  elaters  of  marchantia. 


maturity  the  sporogonium  is  ruptured  at  the  apex,  setting  free  the 
spherical  spores  together  with  numerous  filaments  having  spirally 
thickened  walls.  (Fig.  364.)  These  filaments  are  called  elaters.  When 
drying,  they  exhibit  rapid  movements  by  means  of  which  the  spores 
are  scattered.  The  spores  germinate  and  again  produce  the  thallus  of 
marchantia. 

MOSSES 


If  we  have  followed  carefully  the  development  of  marchantia,  the 
study  of  one  of  the  mosses  will  be  comparatively  easy.  The  mosses 
are  more  familiar  plants  than  the  liverworts.  They  grow  on  trees, 
stones,  and  on  the  soil  both  in  wet  and  dry  places.  One  of  the  com- 
mon larger  mosses,  known  as  Polytrichum  commune,  may  serve  as  an 
example.  This  plant  grows  on  rather  dry  knolls,  mostly  in  the  borders 
of  open  woods,  where  it  forms  large  beds.  In  dry  weather  these  beds 
have  a  reddish  brown  appearance,  but  when  moist  they  form  beautiful 
green  cushions.  This  color  is  due,  in  the  first  instance,  to  the  color  of 
the  old  stems  and  leaves  and,  in  the  second  instance,  to  the  peculiar 


365.   Section  of  leaf  of  Polytrichum  commune. 

action  of  the  green  living  leaves  under  the  influence  of  changing  mois- 
ture-conditions. The  inner  surface  of  the  leaf  is  covered  with  thin, 
longitudinal  ridges  of  delicate  cells  which  contain  chlorophyll.  These 
are  shown  in  cross-section  in  Fig.  365.  All  the  other  tissue  of  the 
leaf  consists  of  thick-walled,  corky  cells  which  do  not  allow  moisture 
to  penetrate.    When  the  air  is  moist  the  green  leaves  spread  out, 


MOSSES 


197 


366.  Section  through  a  receptacle  of 
Polytrichum  commune,  showing 
paraphyses  and  antheridia. 


exposing  the  chlorophyll  cells  to  the  air,  but  in  dry  weather  the  mar- 
gins of  the  leaves  roll  inward,  and  the  leaves  fold  closely  against  the 
stem,  thus  protecting  the  delicate  assimilating  tissue. 

The  antheridia  and  archegonia  of  polytrichum  are  borne  in  groups 
at  the  ends  of  the  branches  on  different 
plants  (many  mosses  bear  both  organs 
on  the  same  branch).  They  are  sur- 
rounded by  involucres  of  characteristic 
leaves  termed  perichsetia  or  perichaial 
leaves.  Multicellular  hairs  known  as 
paraphyses  are  scattered  among  the 
archegonia  and  antheridia.  The  invo- 
lucres with  the  organs  borne  within  them  are  called  receptacles  or,  less 
appropriately,  "moss  flowers."  As  in  marchantia,  the  organs  are  very 
minute  and  must  be  highly  magnified  to  be  studied. 

The  antheridia   are  borne  in  broad   cup-like  receptacles  on   the 
antheridial  plants.    (Fig.  366.)    They  are  much  like 
the  antheridia  of  marchantia,  but  they  stand  free 
among  the  paraphyses  and  are  not  sunk  in  cavities. 
At  maturity  they  burst  and  allow  the  sperm-cells 
or    spermatozoids    to    escape. 
In   polytrichum  when   the  re- 
ceptacles have    fulfilled    their 
function    the    stem    continues 
to  grow  from  the  center  of  the 
cup.    (Fig.  367,  m.)   The  arch- 
egonia are  borne  in  other  re- 
ceptacles  on   different  plants. 
They  are  like  the  archegonia 
of  marchantia  except  that  they 
stand  erect  on  the  end  of  the 
branch. 

The  sporogonium  which  de- 
velops from  the  fertilized  egg 
is  shown  in  Fig.  367,  a,  b.  It 
consists  of  a  long,  brown  stalk 
bearing  the  spore-case  at  its 
summit.  The  base  of  the  stalk 
is  embedded  in  the  end  of  the 
moss  stem  by  which  it  is  nour- 
ished. The  capsule  is  entirely  inclosed  by  a  hairy  cap,  the  calyptra,  b. 
The  calyptra  is  really  the  remnant  of  the  archegonium,  which  for  a  time 


307.   Polytrichum  commune;/,  /,  fertile  plants, 
one  on  the  left  in  fruit;  m,  antheridial  plant. 


198 


STUDIES    IN    CRYPTOGAMS 


increases  in  size  to  accommodate  and  protect  the  young  growing  cap- 
sule. It  is  finally  torn  loose  and  carried  up  on  the  spore-case.  The 
mouth  of  the  capsule  is  closed  by  a  circular  fid,  the  operculum,  having 
a  conical  projection  at  the  center.  The  operculum  soon  drops,  or  it 
may  be  removed,  displaying  a  fringe  of  sixty-four  teeth  guarding  the 
mouth  of  the  capsule. 

This  ring  of  teeth  is  known  as  the  peristome.  In  most  mosses  the 
teeth  exhibit  peculiar  hygroscopic  movements,  i.e.,  when  moist  they 
bend  outwards  and  upon  drying  curve  in  toward  the  mouth  of  the 
capsule.  This  motion,  it  will  be  seen,  serves  to  disperse  the  spores 
gradually  over  a  long  period  of  time. 

Not  the  entire  capsule  is  filled  with  spores.  There  are  no  elaters, 
but  the  center  of  the  capsule  is  occupied  by  a  columnar  strand  of  tis- 
sue, the  columella,  which  expands  at  the  mouth  into  a 
thin,  membranous  disk,  closing  the  entire  mouth  of  the 
capsule  except  the  narrow  annular  chink  guarded  by  the 
teeth.  In  this  moss  the  points  of  the  teeth  are  attached 
to  the  margin  of  the  membrane,  allowing  the  spores  to  sift 
out  through  the  spaces  between  them. 

When  the  spores  germinate,  they  form  a  green, 
branched  thread,  the  protonema.  This  gives  rise  directly 
to  moss  plants,  which  appear  as  little  buds  on  the  thread. 
When  the  moss  plants  have  sent  their  little  rhizoids  into 
the  earth,  the  protonema  dies,  for  it  is  no  longer  necessary 
for  the  support  of  the  little  plants. 

FERNS 


The  adder's  tongue  fern,  Ophioglossum  vulgatum, 
shown  in  Fig.  368,  is  one  of  a  peculiar  type  of  ferns  be- 
longing to  the  family  Ophioglossaceae.  This  plant  has  a 
short,  subterranean  stem  from  which  a  single  frond  unfolds 
each  year.  The  roots  arise  near  the  bases  of  the  leaves. 
The  leaves  are  curiously  divided  into  a  sterile  and  a 
fertile  part,  the  latter  being  a  sporophyll.  The  sterile  part 
has  a  tongue-shaped  blade  which  is  narrowed  to  a  petiole. 

The  young  leaves  are  inclosed  by  the  sheathing  base  of  the  petiole. 

The  growth  is  very  slow,  so  that  it  takes  several  years  for  each  leaf  to 

develop  before  it  is  ready  to  unfold.    During  its  development  each  leaf 

is  sheathed  by  the  one  preceding  it. 

The  sporophyll  is  elevated  on  a  stalk  arising  near  the  base  of  the 

sterile  part  of  the  frond.    The  upper  part  consists  of  a  spike  bearing 


3tis. 


vulgatum. 


FERNS    AND    HORSETAILS  199 

two  rows  of  large  spore-cases  or  sporangia  sunk  in  the  tissue.  At 
maturity  the  sporangia  open  by  transverse  slits  and  discharge  the 
inclosed  spores. 

When  the  spores  germinate  they  produce  subterranean  tuberous 
prothallia  which,  however,  are  rarely  found,  and  of  whose  history  little 
is  known.  They  develop  archegonia  and  antheridia  beneath  the  surface 
of  the  ground,  and  the  fertilized  egg  produces  the  young  fern  plant. 

The  generations  of  the  true  ferns  are  explained  in  Chapter  XXVI. 

EQUISETUMS,  OR  HORSETAILS 

There  are  about  twenty-five  species  of  equisetum,  constituting 
the  only  genus  of  the  unique  family  Equisetacese.  Among  these  E. 
arvense  is  common  on  clayey  and  sandy  soils. 

In  this  species  the  work  of  nutrition  and  that  of  spore-production 
are  performed  by  separate  shoots  from  an  underground  rhizome.  The 
fertile  branches  appear  early  in  spring.  The  stem,  which  is  3  to  6 
inches  high,  consists  of  a  number  of  cylindrical  furrowed  internodes 
each  sheathed  at  the  base  by  a  circle  of  scale-leaves.  The  shoots  are 
of  a  pale  yellow  color.  They  contain  no  chlorophyll,  and  are  nourished 
by  the  food  stored  in  the  rhizome.    (Fig.  369.) 

The  spores  are  formed  on  specially  developed  fertile  leaves  or 
sporophylls  which  are  collected  into  a  spike  or  cone  at  the  end  of  the 
stalk  (Fig.  369,  a).  A  single  sporophyll  is  shown  at  b.  It  consists 
of  a  short  stalk  expanded  into  a  broad,  mushroom-like  head.  Several 
large  sporangia  are  borne  on  its  under  side. 

The  spores  formed  in  the  sporangia  are  very  interesting  and  beau- 
tiful objects  when  examined  under  the  microscope  (X  about  200). 
They  are  spherical,  green  bodies  each  surrounded  by  two  spiral  bands 
attached  to  the  spore  at  their  intersection,  s.  These  bands  exhibit 
hygroscopic  movements  by  means  of  which  the  spores  become  entangled, 
and  are  held  together.    This  is  of  advantage  to  the  plant,  as  we  shall  see. 

All  the  spores  are  alike,  but  sonic  of  the  prothallia  are  better  nour- 
ished and  grow  to  a  greater  size  than  the  others.  The  large  prothallia 
produce  only  archegonia  while  the  smaller  ones  produce  antheridia. 
Both  of  these  organs  are  much  like  those  of  the  ferns,  and  fertilization 
is  accomplished  in  the  same  way.  Since  the  prothallia  are  usually 
dioecious,  the  special  advantage  of  the  spiral  bands  holding  the  Bporee 
together,  so  that  both  kinds  of  prothallia  may  be  in  close  proximity, 
will  be  easily  understood.  As  in  the  fern,  the  fertilized  egg-cell  develops 
into  an  equisetum  plant, 


200 


STUDIES     IN     CRYPTOGAMS 


The  sterile  shoots,  Fig.  369,  st,  appear  much  later  in  the  season. 
They  give  rise  to  repeated  whorls  of  angular  or  furrowed  branches. 
The  leaves  are  very  much  reduced  scales,  situated  at  the  internodes. 
The  stems  are  provided  with  chlorophyll  and  act  as  assimilating  tis- 
sue, nourishing  the  rhizome  and  the  fertile  shoots.  Nutriment  is  also 
stored  in  special  tubers  developed  on  the  rhizome. 


369.  Equisetum  arvense;  st,  sterile  shoot;/,  fertile  shoot  showing  the 
spike  at  a;  b,  sporophyll,  with  sporangia;  s,  spore. 

Other  species  of  equisetum  have  only  one  kind  of  shoot — a  tall, 
hard,  leafless,  green  shoot  with  the  spike  at  its  summit.  Equisetum 
stems  are  impregnated  with  silica  and  they  are  sometimes  used  for 
scouring  floors  and  utensils:  hence  the  common  name  "scouring  rush." 

ISOETES 


Isoetes  or  quillworts  are  usually  found  in  water  or  damp  soil  on 
the  edges  of  ponds  and  lakes.  The  general  habit  of  a  plant  is  seen 
in  Fig.  370,  a.  It  consists  of  a  short,  perennial  stem  bearing  numer- 
ous erect,  quill-like  leaves  with  broad  sheathing  bases.  The  plants 
are  commonly  mistaken  for  young  grasses. 

Isoetes  bears  two  kinds  of  spores,  large  roughened  ones,  the  macro- 
spores,  and  small  ones  or  microspores.    Both  kinds  are  formed  in  spo- 


ISOETES 


201 


rangia  borne  in  aa  excavation  in  the  expanded  base  of  the  leaf.  The  ma- 
crospores  are  formed  on  the  outer,  and  the  microspores  on  the  inner  leaves. 
A  sporangium  in  the  base  of  a  leaf  is  shown  at  b.  It  is  partially  covered 
by  a  thin  membrane,  the  relum.  The  minute  triangular  appendage  at 
the  upper  end  of  the  sporangium  is  called  the  ligvle. 

The  spores  are  liberated  by  the  decay  of  the  spo- 
rangia. They  form  rudimentary  prothallia  of  two 
kinds.  The  microspores  produce  prothallia  with  an- 
theridia,  while  the  macrospores  produce  prothallia  with 
archegonia.  Fertilization  takes  place  as  in  the  mosses 
or  liverworts,  and  the  fertilized  egg-cell,  by  continued 
growth,  gives  rise  again  to  the  isoetes  plant. 


ALTERNATION  OF   GENERATIONS 

In  Chapter  XXVI,  the  alternations  of  generations 
and  the  terms  gametophtye  and  sporophyte  were 
explained.  In  many  of  the  plants  just  studied, 
this  alternation  is  more  clearly  and  beautifully 
marked  than  in  any  other  groups  of  plants. 
In  each  generation,  the  reproductive  body 
(egg  or  spore)  gives  rise  to  a  new  plant- 
form  or  generation  different  from  the  par- 
ent generation.  In  the  liverworts  the 
thallus  produces  the  egg.  The  fertilized 
egg-cell  is  the  beginning  of  a  new  plant, 
but  this  new  plant  is  not  like  the  thallus 
which  produced  the  egg,  nor  does  it  lead 
an  independent  existence.  It  is  the  sporo- 
gonium,  which,  although  it  is  attached  to 
the  thallus,  is  not  a  morphological  part 
thereof.  The  sporogonium  produces  spores.  It  is  the  sporophyte  gen- 
eration of  the  plant,  and  not  until  the  spores  germinate  is  the  thallus 
again  produced.  The  same  is  true  in  the  mosses.  The  "moss  plant" 
produces  the  egg-cells.  It  is  the  gametophyte.  The  fertilized  egg-cell 
develops  into  the  sporophyte — the  spore-case  and  its  stem.  We  can 
pull  the  stem  of  the  capsule  out  of  the  moss  plant  and  thus  separate 
the  sporophyte  from  the  gametophyte. 

The  fungi  and  algse  are  omitted  from  these  remarks.  In  the  former 
there  is  nothing  analogous  to  the  sporophyte  and  the  gametophyte. 
In  alga?  like  spirogyra,  evidently  the  whole  plant  is  a  gametophyte, 


370.  Isoetes  showing  habit  of 
plant  at  a;  b,  base  of  leaf 
showing  sporangium,  velum, 
and  ligule. 


202  STUDIES    IN    CRYPTOGAMS 

and,  since  the  zygospore  germinates  directly  into  a  new  gametophyte, 
there  is  probably  no  sporophyte.  In  some  other  alga*  traces  of  a  sporo- 
phyte  have  been  found,  but  the  discussion  of  these  would  lead  too  far 
for  the  present  purpose. 

In  the  ferns  the  egg-cells  are  developed  on  the  prothallus.  This 
then  is  the  gametophyte.  It  corresponds  to  the  thallus  of  march  antia 
and  to  the  "moss  plant,"  but  it  has  become  much  reduced.  The  plant 
developing  from  the  fertilized  egg-cell  is  the  large  and  beautiful  "fern 
plant"  differentiated  into  stems  and  leaves.  Since  the  fern  plant 
produces  the  spores  directly,  it  is  the  sporophyte  and  corresponds 
to  the  shaft  and  capsule  of  the  mosses.  Both  sporophyte  and  gameto- 
phyte lead  an  independent  existence. 

As  we  pass  on  to  equisetum  and  oscetes,  the  sporophyte  is  still 
more  conspicuous  in  comparison  with  the  gametophyte.  In  isoetes  the 
prothallus  (gametophyte)  is  very  rudimentary,  consisting  only  of  a 
few  cells  remaining  within  the  spore,  which  merely  bursts  to  expose 
the  archegonia  or  to  allow  the  sperm-cells  to  escape.  Moreover,  the 
spores  have  become  differentiated  into  micro-  and  macrospores  corre- 
sponding to  the  pollen  and  embryo-sac  of  higher  plants. 

This  gradual  increase  of  the  sporophyte  and  reduction  of  the  gameto- 
phyte can  be  traced  on  through  the  flowering  plants  in  which  "the 
plant"  is  the  sporophyte,  and  the  gametophyte  is  represented  simply 
by  a  few  cells  in  the  germinating  pollen  grain,  and  in  the  embryo-sac. 


PART  TI- 
THE PLANT  IN  RELATION  TO  ITS 
ENVIRONMENT  AND   TO  MAN 


CHAPTER  XXVIII 

WHERE   PLANTS    GROW 

354.  Environment. — The  circumstances  and  surround- 
ings in  which  an  organism  lives  constitute  its  environment. 
The  environment  comprises  effects  of  soil,  moisture,  tempera- 
ture, altitude,  sunlight,  competition  with  animals  and  other 
plants,  and  the  like.  An  organism  is  greatly  influenced  by 
the  environment  or  conditions  in  which  it  lives.  Not  only 
must  a  plant  live  and  grow  and  multiply  its  kind,  but  it 
must  be  capable  of  withstanding  diverse  environments. 

355.  The  particular  place  in  which  a  plant  grows  is  known 
as  its  habitat  (i.e.,  its  "habitation").  The  habitat  of  a  given 
plant  may  be  a  swamp,  hill,  rock,  sand  plain,  forest,  shore. 
The  plant  inhabitants  of  any  region  are  known  collectively 
as  its  flora.  Thus  we  speak  of  the  flora  of  a  meadow  or  a 
hill  or  a  swamp,  or  of  a  country.  The  word  is  also  used 
for  a  book  describing  the  plants  of  a  region  (as  in  Part  IV). 

356.  Plants  Grow  Where  They  Must.— The  plant  is  not 
able  to  choose  its  environment.  It  has  no  volition.  Its  seeds 
are  scattered,  and  only  a  few  of  them  fall  in  favorable  places. 
The  seeds  make  an  effort  to  grow  even  though  the  places  are 
not  favorable ;  and  so  it  happens  that  plants  are  often  found 
in  places  that  are  little  adapted  to  them.  See  the  fern 
growing  on  a  brick  in  Fig.  74.  Plants  must  grow  in 
unoccupied  places. 

357.  Not  only  do  the  seeds  fall  in  unfavorable  places, 
but  most  places  are  already  occupied.  So  it  comes  that 
plants  grow  where  they  must,  not  always  where  the  conditions 
are  the  most  favorable.  There  are,  of  course,  certain  limits 
beyond  which  plants  cannot  grow.    Water-lilies  can   thrive 

(205) 


372.  Plants  seize  the  first  opportunity  to  grow.    Palisades  of  the  Hudson. 

(206) 


WATER    LIFE  207 

only  i-n  water,  and  white  oaks  only  on  dry  land,  but  it  is 
seldom  that  either  the  water-lily  or  the  oak  finds  the  most 
congenial  place  in  which  to  grow.  Fine  large  plants  of  the  lily 
and  strong  giant  trees  of  the  oak  are  so  infrequent,  as  com- 
pared with  the  whole  number,  that  we  stop  to  admire  them. 

358.  Originally,  plants  probably  were  aquatic,  as  animals 
were.  Much  of  the  earth  was  sea.  Many  plants  are  now 
aquatic,  and  the  larger  number  of  these — as  algae  and  their 
kin — belong  to  the  lower  or  older  forms  of  plant  life.  Many 
plants  of  higher  organization,  however,  as  the  water-lilies, 
have  taken  to  aquatic  life.  True  aquatic  plants  are  those 
that  always  live  in  water,  and  that  die  when  the  water  dries 
up.  They  are  to  be  distinguished  from  those  that  live  on 
shores  or  in  swamps.  Aquatic  plants  may  be  wholly  im- 
mersed or  under  water,  or  partly  emersed  or  standing  above  the 
water.  Most  flowering  aquatic  plants  come  to  the  surface 
to  expand  their  flowers  or  to  ripen  their  fruits.  Some  aquatic 
plants  are  free-swimming,  or  not  attached  to  the  bottom. 
Of  this  kind  are  some  utricularias  or  bladder-worts.  In  some 
waters,  particularly  in  the  ocean,  there  are  enormous  quanti- 
ties of  free-swimming  microscopic  life,  both  animal  and 
vegetable,  which  is  carried  about  by  currents:  this  is  known 
under    the     general  ^>v- 

name    of     plankton  ^^if^^^^^-^-^ 

(Greek    for    "wander-  "  \   ;'fy3ftfei*V*h 

ing"  or  "roaming").  /^\  /  ^V^fvLv?'-'" 

359.  The  general  --^' 


tendency  has  been 
for  plants  to  become 
terrestrial,  or  land-in- 
habiting. Terrestrial 
plants   often  grow  in  ^  v~.  -_- " 

wet  places,  but  never         373"  The  ,ichen  erows  on  the  hard  rock- 
in  water  throughout  their  entire  life;  of  such  are  swamp,  bog 
and  marsh  plants.    Some  plants  have  the  ability  to  grow 


208  WHERE     PLANTS    GROW 

in  standing  water  when  young  and  to  become  terrestrial 
as  the  water  dries  up.  Such  are  amphibious.  Some 
buttercups  are  examples;  mermaid-weed  (Proserpinaca)  is 
another. 

360.  Some  plants  grow  in  very  special  soils  or  special 
localities,  and  consequently  are  infrequent  or  are  confined 
to   certain  well-marked   geographical   regions.     (Fig.   371.) 


374.   Sphagnum  bog,  green  and  living  on  top,  but  dead  and  dying  underneath. 
Sphagnum  moss  is  used  by  nurserymen  and  florists  as  packing  material  for  plants. 

Common  plants  are  those  that  are  able  to  accommodate 
themselves  to  widely  different  environments.  Weeds  are 
examples.  Many  plants  have  become  so  specialized  in  habitat 
as  to  be  parasitic,  saprophytic  or  epiphytic.    (Chap.  XV.) 

361.  Common  plants  often  grow  in  most  unusual  and 
difficult  places.  Note  that  some  weeds  grow  not  only  in 
fields,  but  often  gain  a  foothold  in  chinks  in  logs,  on  rot- 
ting posts,  in  crotches  of  trees,  on  old  straw  stacks,  in  clefts 
and  crannies  of  rocks.  In  moist  climates,  as  in  England, 
plants  often  grow  on  thatched  roofs. 

362.  Plants  may  be  said  to  be  seeking  new  places  in 


SOIL-FORMERS 


209 


which  to  grow.  Whenever  ground  is  cleared  of  vegetation, 
plants  again  spring  up.  The  farmer  plows  the  meadow 
or  pasture,   and  immediately  a  horde  of  weeds  appears. 


375.  The  same  landscape  in  winter  and  in  s 


Any  breach  or  break  in  the  earth's  surface  makes  room 
for  a  new  group  of  plants.  Note  how  the  railway  embank- 
ments and  the  newly  graded  roadsides  take  on  a  covering 
of  vegetation.  Observe  the  ragweed.  Whenever  soil  is 
formed  at  the  base  of  a  cliff,  plants  at  once  secure  a  foothold. 
(Fig.  372.) 

363.  Plants  Aid  in  the  Formation  of  Soil.— This  they 
do  in  two  ways:  by  breaking  down  the  rock;  by  passing  into 
earth  when  they  decay.  Even  on  the  hardest  rocks,  lichens 
and  mosses  may  grow.  (Fig.  373.)  The  rhizoids  eat  away 
the  rock.  A  little  soil  is  formed.  Ferns  and  other  plants  gain 
a  foothold.  The  crevices  are  entered  and  widened.  Slowly 
the  root  acids  corrode  the  stone.  Leaves  and  stems  collect 
on  the  rock  and  decay.  Water  and  frost  lend  their  aid.  As 
the  centuries  pass,  the  rock  is  eaten  away  and  pulverized. 
Note  the  soil  that  collects  on  level  rocks  in  woods  where 
wind  and  rain  do  not  remove  the  accumulations. 

364.  In  bogs  and  marshes  and  on  prairies,  the  remains 
of  plants  form  a  deep  black  soil,  In  bogs  the  vegetable 
matter  is  partially  preserved  by  the  water,  and  it  slowly 
becomes  solidified  into  a  partially  decayed  mass  known  as 


210 


WHERE     PLANTS    GROW 


peat.  When  dug  out  and  dried,  peat  may  be  used  as  fuel. 
Finally  it  may  decay  and  make  a  vegetable  soil  known  as 
muck.  When  thoroughly  decayed,  plants  become  vege- 
table mold  or  humus.  New  plants  grow  on  peat  or  muck, 
and  the  accumulations  year  by  year  tend  to  raise  the  level 
of  the  bog,  and  the  surface  finally  becomes  so  high  as 
to  support  plants  of  the  high  lands.  An  important  agent 
in  the  formation  of  peat  bogs  is  sphagnum  moss.  New 
moss  grows  on  the  old,  and  the  bog  becomes  higher  as 
time  goes  on.    (Fig.  374.) 


376.  A  landscape  devoid  of  vegetation.    Western  United  States. 

365.  Plants  Contribute  to  Scenery. — Aside  from  sky 
and  air,  natural  scenery  depends  chiefly  on  two  things:  the 
physical  contour  of  the  earth;  the  character  of  the  vegeta- 
tion. Contrast  the  aspect  of  winter  and  summer  scenes  as 
expressed  in  vegetation.  (Fig.  375.)  Imagine  any  land- 
scape with  which  you  are  familiar  to  be  devoid  of  plants. 
Compare  Figs.  376  and  377. 


Review. — What  is  meant  by  environment?    By  habitat?    Flora? 
What  determines  where  plants  shall  grow?    What  is  an  aquatic  plant? 


QUESTIONS     ON     WHERE     PLANTS     GROW 


211 


Explain  immersed,  emersed,  free-swimming.  What  is  plankton?  Ex- 
plain terrestrial.  Amphibious.  Why  are  some  plants  rare  or  local? 
Why  are  some  plants  common?  Name  some  unusual  places  in  which 
you  have  seen  plants  growing.  Give  examples  of  how  plants  occupy 
the  new  places.  How  do  plants  aid  in  the  formation  of  soil?  Explain 
what  is  meant  by  peat,  muck,  humus.  How  are  peat  bogs  formed? 
What  relation  have  plants  to  scenery? 


377.  A  landscape  with  vegetation.    Holland. 


CHAPTER  XXIX 

CONTENTION   WITH   PHYSICAL   ENVIRONMENT 

366.  The  Physical  Environment. — We  have  seen  (354) 
that  the  environment  in  which  a  plant  grows  is  made  up 
of  two  sets  of  factors — the  physical  environment  of  climate 
and  soil,  and  the  organic  environment  of  competing  animals 
and  plants. 

367.  Modifications  to  Climate  in  General. — Every  par- 
ticular climate  induces  particular  modifications  in  its  plants. 
There  are  two  general  ways,  however,  in  which  plants  are 
modified  by  climate:  modification  in  the  length  of  the 
period  of  growth;  modification  in  stature.  Any  modification 
of  the  plant,  visible  or  invisible,  that  enables  it  to  grow  in  a 
climate  at  first  injurious  to  it,  is  acclimatization. 

368.  In  short-season  climates,  plants  hasten  their  growth. 
They  mature  quickly.  Indian  corn  may  require  five  or  six 
months  in  which  to  mature  in  warm  countries,  but  only 

three  months  in  very  cold 
countries.  Garden  vegetables 
probably  mature  quicker 
from  the  time  of  planting  in 
the  North  than  in  the  South 
378.  Germination  of  corn  grown  in        when   they   are    raised    from 

New  York  (on  the  left)  and  in  Alabama.  -,  ,1     •  „ 

seeds  grown  m  their  respec- 
tive localities.  Some  seedsmen  think  this  to  be  true  and 
they  like  to  raise  seeds  of  early  varieties  in  the  North,  for 
such  seeds  usually  give  "early"  plants.  Many  plants  that 
are  perennials  in  warm  countries  become  annuals  or  plur- 
annuals  in  cold  countries  (14). 

369.  Plants  are  usually  dwarf  or  smaller  in  stature  in 

(212) 


MODIFICATION    BY    WIND 


213 


short-season  climates.  Indian  corn  is  a  conspicuous  ex- 
ample. As  one  ascends  high  mountains  or  travels  in  high 
latitudes,  he  finds  the  trees  becoming  smaller  and  smaller, 
until  finally  he  passes  beyond  the  regions  in  which  the  trees 
can  grow.  Many  of  the  Esquimaux  doubt  the  statements 
of  travelers  that  there  are  plants  as  high  as  a  man.  In  these 
high  altitudes  and  high  latitudes,  plants  tend  also  to  be- 
come prostrate. 

370.  Plants 
are  Influenced 
by  Wind. — In 
regions  of  strong 
prevailing  winds, 
as  on  lake  and 
sea  shores  and 
on  hills  and 
mountains,  tree- 
tops  develop  un- 
symmetrically 
and  are  heaviest 
on  the  leeward 
side.  (Figs.  379, 
380.)  Observe 
this  fact  in  or- 
chards in  windy 
regions,  and  note 
that  the  most  unsymmetrical  trees  are  those  on  the  exposed 
side  of  the  plantation. 

371.  Trees  often  lean  away  from  the  prevailing  winds. 
The  tips  of  the  branches  of  exposed  trees  usually  indicate 
whether  there  are  strong  prevailing  winds.  (Fig.  381.) 
Observe  trees  in  pastures  and  along  roadsides,  particularly 
in  high  places  and  within  a  few  miles  of  exposed  shores. 
Note  the  tip-top  spray  of  hemlock  trees. 

372.  Plants   are   Profoundly   Influenced   by   Soil. — The 


379.  Evergreen  trees  on  wind- 
Rocky  Mountaii 


214 


PHYSICAL    ENVIRONMENT 


nutrient  supply  varies  with  the  kind  of  soil ;  and  the  supply 
determines  to  a  large  extent  the  character  of  the  individual 
plant.  On  poor  soils  plants  are  small;  on  rich  soils  they  are 
large.  The  difference  between  poor  and  good  yields  of  wheat, 
or  any  other  crop,  is  largely  a  question  of  soil-fertility. 
The  farmer  reinforces  his  poor  soils  by  the  addition  of  ferti- 
lizers, in  order  to  make  his  plants  vary  into  larger  or  more 
productive  individuals. 


380.  One-sided  holly  tree  growing  near  the  ocean.    New  Jersey. 

373.  The  moisture-content  of  the  soil  exerts  a  marked 
influence  on  plants.  We  have  found  (157)  that  a  large 
part  of  the  plant-substance  is  water.  The  water  is  not  only 
itself  food  for  plants,  but  it  carries  nutrients  into  the  plant 
and  transports  them  from  tissue  to  tissue.  However  rich 
a  soil  may  be  in  mineral  nutrients,  it  is  inert  if  it  contains 
no  moisture.  The  character  of  the  plant  is  often  determined 
more  by  the  moisture  in  the  soil  than  by  all  the  other  soil 


MOISTURE    AND    EXPOSURE 


215 


materials.  Note  how  rank  the  plants  are  in  low  places. 
Observe  how  the  weeds  grow  about  the  barn  where  the 
soil  is  not  only  rich  but  where  moisture  is  distributed  from 
the  eaves.  Contrast  with  these  instances  the  puny  plants 
that  grow  in  dry  places.  In  dry  countries  irrigation  is 
employed  to  make  plants  grow  vigorously;  or  the  moisture 
may  be  stored  in  the  soil  by  means  of  deep  preparation  and 
frequent  surface 
tillage  and  other 
dry-farming  meth- 
ods. In  moist  and 
rich  soil  plants 
may  grow  so  fast 
and  so  tall  as  not 
to  be  able  to  with- 
stand the  wind,  as 
in  Fig.  382. 

374.  Plants  are 
Influenced  by  the 
Exposure  of  the 
Place  In  Which 
They  Grow.— The 
particular  site  or 
outlook  is  known 
as  the  exposure  or 
aspect.  The  ex- 
posure, for  example, 
may  be  southward, 
eastward,  bleak,  warm,  cold.  A  favorable  exposure  for 
any  plant  is  one  that  supplies  the  requisite  warmth,  room, 
sunlight,  moisture  and  nutrients,  and  immunity  from  severe 
winds  and  other  destructive  agencies.  Against  the  edge  of 
a  forest  (Fig.  383)  or  at  the  base  of  a  cliff,  certain  plants 
thrive  unusually  well.  Note  the  plants  of  any  kind  grow- 
ing in  different  exposures :  observe  that  they  vary  in  stature, 


381.  A  tree  that  shows  which  way  the  wind  blows. 
Oklahoma. 


382.   "Lodged"  oats.  On  rich  ground  the  grain  is  often  broken  by  wind  and  rain, 
the  plants  having  grown  so  heavy  as  to  be  unable  to  support  themselves. 


3.  The  flowering  dogwood  is  seen  at  its  best  along  the 
margins  of  the  wood  and  in  partially  open  places. 

(216) 


DIFFERENCE    IN    PLANTS  217 

time  of  maturity,  color  of  foliage  and  flowers,  productive- 
ness, size  of  leaves  and  flowers,  longevity. 

Review. — Contrast  physical  and  organic  environments.  How  are 
plants  modified  by  climate?  Define  acclimatization.  Explain  how  time 
of  maturity  is  influenced  by  climate.  Explain  how  climate  influences 
stature.  How  do  winds  affect  plants?  How  are  plants  influenced  by 
soil?   By  soil  moisture?   Exposure? 

Observe  two  or  three  plants  of  any  one  kind  on  your  way  to  school, 
and  note  how  they  differ  from  each  other  in  size,  form,  branching, 
color,  earliness  or  lateness,  productiveness  and  other  characters:  are 
you  able  to  correlate  these  differences  with  the  conditions  in  which 
the  plants  grow? 


CHAPTER  XXX 

COMPETITION   WITH   FELLOWS 

375.  The  Fact  of  Struggle  for  Existence.— We  have 
seen  (Chapter  IX)  that  branches  contend  amongst  them- 
selves for  opportunity  to  live  and  grow.  Similarly,  separate 
plants  contend  with  each  other.  We  shall  observe  that  this 
is  true;  and  we  are  compelled  to  believe  it  by  considering 
the  efforts  that  all  plants  make  to  propagate  themselves. 
The  earth  is  filled  with  plants.  It  is  chiefly  when  plants 
die  or  are  killed  that  places  are  made  for  others.  Every  one 
of  these  plants  puts  forth  its  utmost  effort  to  prepetuate  its 
kind.  It  produces  seeds  by  the  score  or  even  by  the  thousand. 
In  some  cases  it  propagates  also  by  means  of  vegetative 
parts.  If  the  earth  is  full  and  if  every  plant  endeavors  to 
multiply  its  kind,  there  must  be  struggle  for  existence. 

376.  The  effects  of  struggle  for  existence  are  of  three 
general  categories:  (1)  the  seed  or  spore  may  find  no  oppor- 
tunity to  grow;  (2)  sooner  or  later  the  plant  may  be  killed; 
(3)  the  plant  may  vary,  or  take  on  new  characters,  in  response 
to  the  conditions  in  which  it  grows.  Consider  the  crop  of 
seeds  that  any  plant  produces:  how  many  germinate? 
How  many  of  the  young  plants  reach  maturity?  Note  the 
profusion  of  seedlings  under  the  maples  and  elms,  and  then 
consider  how  few  maple  and  elm  trees  there  are.  Count  the 
seeds  on  any  plant  and  imagine  that  each  one  makes  a  plant : 
where  will  all  these  new  plants  find  a  place  in  which  to  grow? 

377.  What  Struggle  for  Existence  Is. — Struggle  for 
existence  with  fellows  is  competition  for  room  or  space, 
for  nutrients  and  moisture  in  the  soil,  for  light.  We  may  con- 
sider examples  in  each  of  these  three  categories. 

(218) 


384.  There  is  no  opportunity  for  weeds  in  a  good  field  of  wheat. 


- 

j 

* .  £^*C**)fc 

-  Sfi^iF 

-«j3 

Hm  '^^jJJKSfll 

Kr" 

*>■  t  C  litf.  * ..  v  it . \£ 

fc        fe        :•' 

&^Mj 

fEP^Lk- 

lit- 

(219) 


220 


COMPETITION    WITH    FELLOWS 


378.  If  the 
earth  is  filled 
with  plants, 
there  must  be 
sharp  competi- 
tion for  every 
inch  of  its  sur- 
face. If  any 
good  soil  is  not 
populated  with 
plants,  it  is  usu- 
ally because  it 
has  recently 
been  moved.  If  the  farmer  does  not  move  or  till  his 
soil  frequently,  various  plants  get  a  foothold,  and  these 
plants  he  calls  weeds.  Determine  how  much  room  an  apple 
tree,  or  other  plant,  occupies:  then  calculate  how  much 
space  would  be  required  for  all  the  seedlings  of  that  tree  or 
plant.  The  greater  the  population  of  any  area,  the  less  chance 


The  tree  has  appropriated  the  food  and  moisture 
that  a  large  area  remains  bare  of  vegetation. 


387.   Low  shade-loving  plants  on  the  forest  floor. 


UNLIKE    PLANTS    GROW    TOGETHER 


221 


have  other  plants  to  gain  a  foothold.  When  the  wheat  com- 
pletely covers  the  ground,  as  in  Fig.  384,  there  are  no  weeds 
to  be  seen. 

379.  Plants  of  different  form  and  habit  may  grow 
together,  and  thereby  the  area  may  support  more  plants 
than  would  be  possible  if  only  one  kind  were  growing  on 
it.    This  principle  has  been  called  by  Darwin  the  divergence 


388.  A  primeval  pine  forest. 
Along  the  roadway  foreign  vegetation  has  come  in.    Michigan. 

of  character.  When  an  area  is  occupied  by  one  kind  of 
plant,  another  kind  may  grow  between  or  beneath.  Only 
rarely  do  plants  of  close  botanical  relationship  grow  to- 
gether in  compact  communities.  A  field  that  is  full  of  corn 
may  grow  pumpkins  between.  (Fig.  385.)  A  full  meadow 
may  grow  white  clover  in  the  bottom.  Herbs  may  grow 
on  the  forest  floor.  When  an  orchard  can  support  no  more 
trees,  weeds  may  grow  beneath. 


222  COMPETITION     WITH     FELLOWS 

380.  We  have  learned  that  the  plant  may  possess  an  ex- 
tensive root-system  (25,  26).  The  plant  that  is  first  estab- 
lished appropriates  the  nutrients  to  itself,  and  newcomers 
find  difficulty  in  gaining  a  foothold.   Note  the  bare  area  near 


On  the  top  of  an  evergreen  forest. 


the  large  tree  in  Fig.  386.  Recall  how  difficult  it  is  to  make 
plants  grow  when  planted  under  trees.  This  is  partly  due 
to  the  intercepting  of  the  rain  by  the  tree-top,  partly  to  shade, 
and  partly  to  lack  of  available  food  and  moisture  in  the  soil, 
and  perhaps  partly  to  unknown  factors.  The  farmer  knows 
that  he  cannot  hope  to  secure  good  crops  near  large  trees, 


CLIMBERS   AND   SHADE-LOVERS 


223 


even  beyond  the  point  at 
which  the  trees  intercept 
the  rain  and  light.  It  is 
difficult  to  establish  new 
trees  in  the  vacancies  in  an 
old  orchard. 

381.  In  Chapter  VIII  we 
studied  the  relation  of  the 
plant  and  its  parts  to  sun- 
light. Plants  also  compete 
with  each  other  for  light. 
Plants  climb  to  get  to  the 
light  (Chapter  XVIII).  (Fig. 
77.)  Some  plants  have  be- 
come so  modified  as  to 
grow  in  subdued  or  transmitted  light,  but  no  green 
can  grow  in  darkness.  The  low  plants  in  forests  are 
lovers.  (Fig.  387.)  Note  the  plants  that  seem  to  be 
lovers   and  those  that  prefer   full   sunlight.    Some 


390.   The  tell-tale  pine 


plants 
shade- 
shade- 
plants 


224 


COMPETITION    WITH    FELLOWS 


are  so  constituted  as  to 
grow  well  in  both  sun  and 
shade.  Most  ferns  are 
shade-lovers. 

382.  In  the  midst  of 
dense  plant  populations, 
each  individual  grows  up- 
wards for  sunlight.  Thus 
are  forests  made:  the  com- 
peting trees  become  long 
slender  boles  with  a  mantle 
of  foliage  at  the  top.  The 
side  branches  do  not  de- 
velop or  they  die  for  lack  of 
light  and  food,  and  they  fall 
from  decay  or  are  broken 
by  storm;   the  wounds  are 

healed,  and  the  bole  becomes  symmetrical  and  trim.    Fig. 

388  shows  the  interior  of  a  primeval  pine  forest.    Note  the 


392.  The  forest  center.  Looking  from  the 
woods,  with  the  forest  rim  shown  in 
Fig.  391  seen  in  the  distance. 


The  foliage  bank  of  a  tangle. 


COMPETITION    IN    THE    FOREST 


225 


bare  trunks  and  the  sparse  vegetation  on  the  dim  forest  floor. 
Fig.  389  is  the  top  of  a  great  forest.  With  these  pictures 
compare  Figs.  79  and  80.  Fig.  384  shows  a  deep  wheat 
forest.  A  lone  survivor  of  a  primeval  forest  is  shown  in 
Fig.  390.  In  dense  plantations,  plants  tend  to  grow  to  a 
single  stem.  When  these  same  plants  are  grown  in  open 
or  cultivated  grounds,  they  often  become  bushy  or  develop 


394.   View  just  inside  the  tangle. 


more  than  one  trunk.    In  what  places  have  you  seen  trees 
with  more  than  one  trunk? 

383.  On  the  margins  of  dense  populations,  each  indi- 
vidual grows  outwards  for  sunlight.  Note  the  dense  forest 
rim:  then  plunge  through  it,  and  stand  by  the  tall  bare 
trunks.  Figs.  391,  392,  show  these  two  views  of  the  same 
forest.  Note  the  kinds  of  trees  and  other  plants  that  grow 
in  areas  similar  to  those  depicted  in  these  illustrations. 
Note  the  dense  wall  of  foliage  in  Fig.  393,  and  the  thin  brushy 
area  just  behind  it  in  Fig.  394.  Observe  the  denser  and  greener 
foliage  on  the  outside  rows  in  thick  orchards.  Consider  how 


.  A  hydrophytic  society.    New  York. 


396.  A  mesophytic  society.    Michigan. 

(226) 


PLANTS   REACT   TO    LIGHT  227 

the  plants  extend  over  the  borders  in  dense  flower-beds.  Note 
where  the  best-foliaged  plants  are  in  the  greenhouse.  Notice 
the  foliage  on  the  outer  rows  in  a  very  thick  cornfield.  Ob- 
serve how  plants  nearest  to  buildings  reach  outward  for  the 
light  and  room. 

Review. — Why  is  there  struggle  for  existence?  How  does  it  affect 
plants?  Tell  what  it  is.  How  do  plants  compete  for  space?  What 
is  meant  by  the  phrase  "divergence  of  character?"  Give  examples. 
How  do  plants  compete  for  nutrients  and  water  from  the  soil?  In  what 
respects  have  plants  become  modified  to  the  light  relation?  How  do 
plants  grow  in  dense  plantations?  On  the  margins  of  these  planta- 
tions? You  know  some  tree  or  other  plant:  describe  how  it  is  consti- 
tuted to  compete  with  its  fellows. 


CHAPTER  XXXI 

PLANT   SOCIETIES 

384.  What  Plant  Societies  Are. — In  the  long  course 
of  evolution,  in  which  plants  have  been  accommodating 
themselves  to  the  varying  conditions  in  which  they  are 
obliged  to  grow,  they  have  become  modified  to  every 
different  environment.  Certain  plants,  therefore,  may  live 
together  or  near  each  other,  all  enjoying  the  same  conditions 
and  surroundings.  These  aggregations  of  plants  adapted 
to  similar  conditions  are  known  as  plant  societies. 

385.  Moisture  and  temperature  are  the  leading  factors 
in  determining  plant  societies.  The  great  geographical 
societies  or  aggregations  of  the  plant  world  are  for  con- 
venience associated  chiefly  with  the  moisture-supply.  These 
are:  (1)  hydrophytic  or  wet-region  societies,  comprising 
aquatic  and  bog  vegetation  (Fig.  395);  (2)  xerophytic  or 
arid-region  societies,  comprising  desert  and  much  sand-region 
vegetation  (Fig.  371);  (3)  mesophytic  or  mid-region  societies, 
comprising  the  vegetation  in  intermediate  conditions  (Fig. 
396).  Mesophytic  vegetation  is  characteristic  of  most  regions 
that  are  fitted  for  agriculture.  The  halophytic  or  salt-loving 
societies  are  also  distinguished,  comprising  the  seashore  and 
salt-area  vegetation.  Much  of  the  characteristic  scenery  of 
any  place  is  due  to  its  plant  societies  (365).  Xerophytic 
plants  usually  have  small  and  hard  leaves,  apparently  to 
prevent  too  rapid  transpiration.  Usually,  also,  they  are 
characterized  by  stiff  growth,  hairy  covering,  spines,  or  a 
much-contracted  plant-body,  and  often  by  large  under- 
ground parts  for  the  storage  of  water.  Halophytic  plants 
are  often  fleshy. 

(228) 


PLACE-VEGETATION 


229 


386.  Plant  societies  may  also  be  distinguished  with  refer- 
ence to  latitude  and  temperature.  There  are  tropical  socie- 
ties, temperate-region  societies,  boreal  or  cold-region  societies. 
With  reference  to  altitude,  societies  might  be  classified  as 


lowland  (which  are  chiefly  hydrophytic),  intermediate  (chiefly 
mesophytic),  svbalpine  or  mid-mountain  (which  are  chiefly 
boreal),  alpine  or  high-mountain. 

387.  The  above  classifications  have  reference  chiefly  to 
great  geographical  floras  or  societies.  But  there  are  societies 
within  societies.  There  are  small  societies  coming  within 
the  experience  of  every  person  who  has  ever  seen  plants 
growing  in  natural  conditions.  There  are  roadside,  fence- 
row,  lawn,  thicket,  pasture,  dune  ( Kig.  397),  woods,  cliff, 
barn-yard,  corn-field  societies.  Every  different  place  has  its 
characteristic  vegetation.  Note  the  smaller  societies  in  Figs. 
395  and  390.  In  the  former  is  a  water-lily  society  and  a 
cat-tail  society.  In  the  latter  there  are  grass  and  bush  and 
woods  societies. 


230  PLANT    SOCIETIES 

388.  Some  Details  of  Plant  Societies. — Societies  may  be 
composed  of  scattered  and  intermingled  plants,  or  of  dense 
clumps  or  groups  of  plants.  Dense  clumps  or  groups  are 
usually  made  up  of  one  kind  of  plant,  and  they  are  then  called 
colonies.  Colonies  of  most  plants  are  transient:  after  a  short 
time  other  plants  gain  a  foothold  amongst  them,  and  an 
intermingled  society  is  the  outcome.  Marked  exceptions  to 
this  are  grass  colonies  and  forest  colonies,  in  which  one  kind 
of  plant  may  hold  its  own  for  years  and  centuries. 


The  return  to  forest.    Bushes  and  trees  now  begin  to  crowd. 


389.  In  a  large  newly  cleared  area,  plants  usually  first 
establish  themselves  in  dense  colonies.  Note  the  great  patches 
of  nettles,  jewel-weeds,  smart-weeds,  clot-burs,  and  others  in 
recently  cleared  but  neglected  swales,  also  the  fire-weeds 
in  recently  burned  areas,  the  rank  weeds  in  the  neglected 
garden,  and  the  ragweeds  and  May-weeds  along  the  recently 
worked  highway.  The  competition  amongst  themselves 
and  with  their  neighbors  finally  breaks  up  the  colonies,  and 
a  mixed  and  intermingled  flora  is  generally  the  result. 

390.  In  many  parts  of  the  world  the  general  tendency 
of  neglected  areas  is  to  run  into  forest.  A  large  number  of 
different  plants  begin  growth  in  a  cleared  area.  Here  and 
there  bushes  gain  a  foothold.   Young  trees  come  up:  in  time 


THE    RETURN    TO     FOREST 


231 


these  shade  the  bushes  and  gain  the  mastery.  Sometimes  the 
area  grows  to  poplars  or  birches,  and  people  wonder  why  the 
original  forest  trees  do  not  return;  but  these  forest  trees  may 
be  growing  unobserved  here  and  there  in  the  tangle,  and  in 
the  slow  processes  of  time  the  poplars  perish — for  they  are 
short-lived — and  the  original  forest  may  be  replaced. 
Whether  one  kind  of  forest  or  another  returns  will  depend 
largely  on  the  kinds  that  are  most  seedful  in  that  vicinity 
and  which  therefore,  have  sown  themselves  most  profusely. 
Much  depends,  also,  on  the  kind  of  undergrowth  that  first 
springs  up,  for  some  young  trees  can  endure  more  or  less 
shade  than  others.  Fig.  398  shows  an  early  stage  in  the 
return  to  forest. 

391.  Pasturing  and  mowing  tend  to  keep  an  area  in  grass. 
This  is  because  the  grass  will  thrive  when  the  tops  are 
repeatedly  taken  off,  whereas  trees  will  not.  Note  that  the 
wild  herbs  and  bushes  and  trees  persist  along  the  fences  and 
about  old  buildings,  where  animals  and  mowing  machines 
do  not  take  them  off.  A  sod  society  means  grazing  or  mowing. 
Consider  Figs.  110,  399,  400.  The  farmer  keeps  his  wild 
pastures  "clean"  by  turning  in  sheep:  the  sheep  are  fond  of 
browsing. 

392.  Some  plants 
associate.  They 
grow  together.  This 
is  possible  largely  be- 
cause they  diverge 
or  differ  in  character 
(379).  Plants  associ- 
ate in  two  ways:  by 
growing  side  by  side; 
by  growing  above  or 
beneath.  In  sparsely 
populated     societies 

\aS      in       r  lg.      4  U  1 )  trees  find  refuge  from  the  mowing  machine. 


232 


PLANT    SOCIETIES 


plants  may  grow 
along  side  each 
other.  In  most 
cases,  however, 
there  is  overgrowth 
and  undergrowth : 
one  k  i  n  d  grows 
beneath  another. 
Plants  that  endure 
shade  (381)  are 
usually  under- 
growths.  In  a  cat- 
tail swamp,  grasses 
and  other  narrow- 
leaved  plants  grow 
in  the  bottom,  but 
they  are  usually  un- 
seen by  the  casual 
observer.  Search 
the  surface  of  the 

400.  The  farmer  mows  part  of  his  roadside.  ground  in  any  SWale 

or  meadow.   Note  the  undergrowth  in  woods  or  under  trees. 
(Fig.  402.)    Observe  that  in  pine  and  spruce  forests  there 
is  almost  no  undergrowth, 
because  conditions  are  not 
favorable.    (Fig.  388.) 

393.  On  the  same  area 
the  societies  may  differ  at 
different  times  of  the  year. 
There  are  spring,  summer 
and  fall  societies.  The 
knoll  that  is  cool  with 
grass  and  strawberries  in 
June  may  be  aglow  with 
other  plants  in  September. 


401.   An  aquatic  society  in  which  several 
kinds  of  plants  grow  side  by  side. 


THE    LANDSCAPE 


233 


402.  Overgrowth  and  undergrowth  in  three  serie; 
— trees,  bushes,  grass. 


If  the  bank  is  examined  in  May,  look  for  the  young  plants 
that  are  to  cover  it  in  July  and  October;  if  in  September, 
find  the  dead  stalks  of  the  flora  of  May.  What  succeeds 
the  skunk  cabbage,  hcpaticas,  trilliums,  phlox,  violets,  butter- 
cups of  spring? 
What  precedes  the 
w  i  1  d  sunflowers, 
ragweed,  asters, 
and  goldenrod  in 
fall? 

394.  In  lands 
that  gradually  rise 
from  wet  to  dry, 
the  societies  may 
take  the  form  of 
belts  or  zones.  Start- 
ing at  a  shore,  walk 
back  into  the  high 
land;  note  the  changes  in  the  flora.  Three  zones  are  shown 
in  Fig.  403. 

395.  To  a  large  extent,  the  color  of  the  landscape  is 
determined  by  the  character  of  the  plant  societies.  Ever- 
green societies  remain  green,  but  the  shade  of  green  varies 
from  season  to  season ;  it  is  bright  and  soft  in  spring,  becomes 
dull  in  midsummer  and  fall,  and  often  assumes  a  dull  yel- 
low-green in  winter.  Deciduous  societies  vary  remarkably 
in  color — from  the  dull  browns  and  grays  of  winter  to  the 
brown-greens  and  olive-greens  of  spring,  the  staid  greens  of 
summer,  and  the  brilliant  colors  of  autumn. 

396.  The  autumn  colors  are  due  to  intermingled  shades 
of  green,  yellow  and  red.  The  coloration  varies  with  the 
kind  of  plant,  the  special  location  and  the  season.  Even 
in  the  same  species  or  kind,  individual  plants  differ  in  color; 
and  this  individuality  usually  distinguishes  the  plant  year 
by  year.    That  is,  an  oak  that  is  maroon-red  this  autumn 


234 


PLANT    SOCIETIES 


is  likely  to  exhibit  that  color  every  year.  The  autumn  color 
is  associated  with  the  natural  maturity  and  death  of  the 
leaf,  but  it  is  most  brilliant  in  long  and  open  falls — largely 
because  the  foliage  ripens  more  gradually  and  persists  longer 
in  such  seasons.    It  is  probable  that  the  autumn  tints  are 

of  no  utility  to  the  plant. 
The  yellows  seem  to  be 
due  in  part  to  the  break- 
ing down  and  disorganiza- 
tion of  the  chlorophyll. 
Some  of  the  intermediate 
shades  are  probably  due 
to  the  unmasking  or  liber- 
ating of  normal  cell  color- 
bodies  which  are  covered 
with  chlorophyll  or  ob- 
scured by  it  in  the  grow- 
ing season.  The  reds  are 
due  to  changes  in  the  color 
of  the  cell-sap,  or  to  the 
unmasking  of  the  red  by 
the  disintegration  of  the 
chlorophyll.  Autumn 
colors  are  not  caused  by 
frost.  Because  of  the  long, 
dry  falls  and  the  great 
variety  of  plants,  the 
autumnal  color  of  the 
American   landscape   is  phenomenal. 

397.  Ecology. — The  study  of  the  relationships  of  plants 
and  animals  to  each  other  and  to  seasons  and  environ- 
ments is  known  as  ecology  (still  written  cecology  in  some 
dictionaries).  All  the  discussions  in  Part  II  of  this  book 
are  really  different  phases  of  this  subject.  It  considers 
the  habits,  habitats  and  modes  of   life  of  living  things— 


403.  Three  society  zones- 
forest. 


-bog,  forest  rim, 


ECOLOGY  235 

the  places  in  which  they  grow,  how  they  migrate  or  are 
disseminated,  means  of  collecting  food,  their  times  and  sea- 
sons of  flowering,  reproduction,  and  the  like. 

Review. — What  is  a  plant  society?  Why  do  plants  grow  in 
societies?  Name  societies  that  are  determined  chiefly  by  moisture. 
What  societies  are  most  abundant  where  you  live?  Name  those  de- 
termined by  latitude  and  altitude.  Name  some  small  or  local  societies. 
What  are  colonies?  Where  are  they  most  marked?  Why  do  they 
tend  finally  to  break  up?  How  are  societies  composed  when  colonies 
are  not  present?  How  do  forests  arise  on  cleared  areas?  What  effect 
have  pasturing  and  mowing?  How  do  plants  associate?  What  is 
undergrowth  and  overgrowth?  Explain  how  societies  may  differ  at 
different  times  of  the  year.  What  are  zonal  or  belt  societies?  Discuss 
autumn  colors.  What  is  ecology? 

Note. — One  of  the  best  of  all  subjects  for  school  instruction  in 
botany  is  the  study  of  plant  societies.  It  adds  definiteness  and  zest 
to  excursions.  Let  one  excursion  be  confined  to  one  or  two  societies. 
Visit  one  day  a  swamp,  another  day  a  forest,  another  a  pasture  or 
meadow,  another  a  roadside,  another  a  weedy  field,  another  a  cliff 
or  ravine.  Visit  shores  whenever  possible.  Each  pupil  should  be 
assigned  a  bit  of  ground — say  10  or  20  feet  square — for  special  study. 
He  should  make  a  list  showing  (1)  how  many  kinds  of  plants  it  con- 
tains, (2)  the  relative  abundance  of  each.  The  lists  secured  in  different 
regions  should  be  compared.  It  does  not  matter  if  the  pupil  does  not 
know  all  the  plants.  He  may  count  the  kinds  without  knowing  the 
names.  It  is  a  good  plan  for  the  pupil  to  make  a  dried  specimen  of 
each  kind  for  reference.  The  pupil  should  endeavor  to  discover  why  the 
plants  grow  as  they  do.    Challenge  every  plant  society. 


CHAPTER    XXXII 

VARIATION  AND   ITS   RESULTS 

398.  The  Fact  of  Variation. — No  two  plants  are  alike 
(16).  In  size,  form,  color,  weight,  vigor,  productiveness, 
season  or  other  characters,  they  differ.  The  most  usual  form 
of  any  plant  is  considered  to  be  its  type,  that  is,  its  repre- 
sentative form.  Any  marked  departure  from  this  type  is  a 
variation,  that  is,  a  difference. 

399.  The  Kinds  of  Variations. — Variations  are  of  many 
degrees.  The  differences,  in  any  case,  may  be  so  slight  as  to 
pass  unnoticed,  or  they  may  be  so  marked  as  to  challenge 
even  the  casual  observer.  If  a  red-flowered  plant  were  to 
produce  flowers  in  different  shades  of  red,  the  variation 
might  not  attract  attention;  but  if  it  were  to  produce 
white  flowers,  the  variation  would  be  marked.  When- 
ever  the   variation   is   so   marked   and   so  constant   as   to 

be  worth  naming  and  describ- 
ing, it  is  called  a  variety  in 
descriptive  botany.  If  the 
variation  is  of  such  charac- 
ter as  to  have  value  for  cul- 
tivation, it  is  called  an  agri- 
cultural or  horticultural  va- 
riety. There  is  no  natural 
line  of  demarcation  between 
those  variations  that  chance 
to  be  named  and  described 
as  varieties  and  those  that  do 
not.  Varieties  are  only  named 

404.  An  arborvitse  tree,  from  which  seeds  J 

were  taken  one  day.  Variations. 

(236) 


SEED-    AND    BUD-VARIETIES  237 

400.  Variations  may  arise  in  three  ways:  (1)  directly 
from  seeds;  (2)  directly  from  buds;  (3)  by  a  slow  change 
or  a  lack  of  development  in  the  entire  plant  after  it  has  begun 
to  grow. 

401.  Variations  arising  from  seeds  are  seed-variations; 
those  that  chance  to  be  named  and  described  are  seed- 
varieties.  Never  does  a  seed  exactly  reproduce  its  parent; 
if  it  did,  there  would  be  two  plants  alike.  Neither  do  any 
two  seeds,  even  from  the  same  fruit,  ever  produce  plants 
exactly  alike.  Even  though  the  seedlings  resemble  each 
other  so  closely  that  people  say  they  are  the  same,  never- 


405.  The  progeny  of  the 

seeds  of  the  tree  shown  in  Fig.  404. — 

No  two  plants  alike. 

theless  they  will  be  found  to  vary  in  size,  number  of  leaves, 
shape,  or  other  features.    Study  Figs.  404  and  405. 

402.  Variations  arising  directly  from  buds,  rather  than 
from  seeds,  are  bud-variations,  and  the  most  marked  of 
them  may  be  described  and  named  as  bud-varieties.  We 
have  learned  in  Chapter  V  how  the  horticulturist  propagates 
plants  by  means  of  buds :  not  one  of  these  buds  will  repro- 
duce exactly  the  plant  from  which  it  was  taken.  We  have 
already  discovered  (17,  119)  that  no  two  branches  are  alike, 
and  every  branch  springs  from  a  bud.  Bud-variation  is 
usually  less  marked  than  seed-variation,  however;  yet  now 
and  then  one  branch  on  a  plant  may  be  so  unlike  every  other 
branch  that  the  horticulturist  selects  buds  from  it  and 
endeavors  to  propagate  it.  "Weeping"  or  pendent  branches 
sometimes  appear  on  upright  trees;  nectarines  sometimes 
are  borne  on  one  or  more  branches  of  a  peach  tree,  and 


238 


VARIATION    AND     ITS    RESULTS 


peaches  may  be  borne  on  nectarine  trees;  russet  apples 
are  sometimes  borne  on  Greening  apple  trees;  white  roses 
are  sometimes  found  on  red-flowered  plants. 

403.  Frequently  a  plant  begins  a  new  kind  of  varia- 
tion long  after  germination,  even  after  it  has  become  well 

established.  It  is  on 
this  fact  that  success- 
ful agriculture  de- 
pends, for  the  farmer 
makes  his  plants 
better  by  giving  them 
better  nutrition  and 
care:  and  betterment 
(like  deterioration)  is 
only  a  variation  as 
compared  with  the 
average  plant.  Plants 
that  start  to  all 
appearances  equal 
may  end  unequal: 
some  may  be  tail  and 

vigorous,  others  may  be  weak,  others  may  be  dwarf:  some 

will  be  worth  harvesting  and  some  will  not. 

404.  The  Causes  of  Variations. — Variations  are  induced 
by  several,  and  perhaps  many,  causes.  One  class  of  origin 
lies  in  the  environment,  and  another  lies  in  the  tendencies 
derived  from  parents.  Of  the  environmental  causes  of  vari- 
ation, the  chief  is  probably  food-supply.  Good  agriculture 
consists  largely  in  increasing  the  food-supply  for  plants — by 
giving  each  plant  abundant  room,  keeping  out  competing 
plants,  tilling  the  soil,  adding  fertilizers.  (Fig.  406.)  Another 
strong  environmental  factor  is  climate  (Chapter  XXIX). 
It  is  very  difficult  to  determine  the  exact  reasons  for  any 
variation.  There  is  much  difference  of  opinion  respecting 
the  causes  of  variation  in  general,    The  extent  of  variation 


406.  Variation. — Big  and  little  redroot  pigweeds 
of  the  same  kind. 


THE    CASE    OF    THE    PIGWEEDS  239 

apparently  due  to  food-supply  is  illustrated  in  Fig.  406.  The 
two  weeds  grew  five  feet  apart,  one  in  hard  soil  by  a  Avalk, 
the  other  near  a  compost  pile.  They  were  of  similar  age. 
One  weighed  \  oz.;  the  other  4j  lbs.,  or  136  times  as  much. 

405.  Heredity. — Marked  variations  tend  to  be  perpet- 
uated. That  is,  immediate  offspring  are  likely  to  retain 
some  of  the  peculiarities  of  their  parents.  This  passing  over 
of  characteristics  from  parent  to  offspring  is  heredity. 
By  "selecting  the  best"  for  seed  the  farmer  maintains  and 
improves  his  crops.  It  is  said  that  "like  produces  like." 
This  is  true  of  the  general  or  average  features,  but  we  have 
seen  that  the  reproduction  is  not  exact.  It  is  truer  to  say  that 
similar   produces   similar.     Fig.    407   represents   a   marked 


407.  The  progeny  of  little  and  big  plants. 

case  of  heredity  of  special  characters.  The  plants  on  the 
right  grew  from  a  parent  24  in.  high  and  30  in.  broad.  Those 
on  the  left  grew  from  one  12  in.  high  and  9  in.  broad.  (For 
a  history  of  these  parents  see  "Survival  of  the  Unlike," 
p.  261.) 

406.  Selection. — There  is  intense  struggle  for  existence: 
there  is  universal  variation:  those  variations  or  kinds  live 
that  are  best  fitted  to  live  under  the  particular  conditions. 


240  VARIATION    AND    ITS    RESULTS 

This  persistence  of  the  best-fitted  and  loss  of  the  least- 
fitted  is  the  process  designated  by  Darwin's  phrase  "natural 
selection"  and  by  Spencer's  "survival  of  the  fittest."  Natural 
selection  is  also  known  as  Darwinism. 

407.  By  a  similar  process,  the  cultivator  modifies  his 
plants.  He  chooses  the  variations  that  please  him,  and  from 
their  offspring  constantly  selects  for  seed-bearing  those 
that  he  considers  to  be  the  best.  In  time  he  has  a  new 
variety.  Plant-breeding  consists  chiefly  of  two  factors 
or  processes;  producing  a  variation  in  the  desired  direction; 
selecting,  until  the  desired  variety  is  secured. 

408.  Evolution. — Variation,  heredity,  natural  selection 
and  other  agencies  bring  about  a  gradual  change  in  the 
plant  kingdom;  this  change  is  evolution.  The  hypothesis 
that  one  form  may  give  rise  to  another  is  now  universally 
accepted  amongst  investigators;  but  whether  the  vegetable 
kingdom  has  all  arisen  from  one  starting  point  is  unknown. 
Only  a  few  of  the  general  lines  of  the  unfolding  of  the  vege- 
table kingdom,  with  numberless  details  here  and  there,  have 
been  worked  out.  Not  every  form  or  kind  of  plant  can  be 
expected  ever  to  vary  into  another  kind.  Some  kinds  have 
nearly  run  their  course,  and  are  undergoing  the  age-long 
process  of  extinction.  It  is  thought,  however,  that  every 
kind  of  plant  now  living  has  been  derived  from  some  other 
kind.  Evolution  is  still  in  progress.  Variation  and  heredity 
are  two  of  the  most  important  facts  in  organic  nature. 

Review. — What  is  a  variation?  A  variety?  Agricultural  vari- 
ety? How  many  variations  arise?  Explain  each  of  the  three  categories. 
What  are  some  of  the  apparent  causes  of  variation?  What  is  heredity? 
Selection?    What  are  essentials  in  plant-breeding?    What  is  evolution? 


CHAPTER    XXXIII 


WEEDS 


409.  Plants  compete  with  each  other.  It  happens  that 
some  of  the  competitors  are  specially  useful  to  man,  and 
he  endeavors  to  protect  them;  and  in  protecting  them  he 
destroys  the  plants  that  tend  to  crowd  them  out.  Certain 
plants  have  the  habit  of  occupying  places  that  are  desired 
for  other  uses.    A  weed  is  a  plant  that  is  not  wanted. 

410.  Weeds,  therefore,  are  of  two  general  classes:  those 
that  interfere  with  plants  that  man  ctdtivates;  those  that 
inhabit  unoccupied  and  waste  places.  Cer- 
tain kinds  of  plants  are  specially  adapted 
to  hold  their  own  in  such  competition  or  to 
invade  open  places;  and  these  plants  are 
particularly  known  as  weeds.  But  any  plant 
may  be  a  weed,  if  it  is  out  of  place  or  is 
not  wanted.  June-grass  is  a  weed  in  a  corn- 
field, but  not  in  a  pasture  or  lawn.  Dan-  Sy 
delion  and  purslane  are  commonly  regarded  § 
as  real  weeds,  yet  they  are  sometimes  culti- 
vated for  "greens,"  and  they  then  become 
a  crop.  When  any  crop  is  too  thick,  the 
weaker  and  useless  plants  interfere  with  the 
others  and  become  weeds.  Thus  some  of 
the  corn  plants  may  be  weeds  in  a  cornfield. 
If  one  were  growing  a  forest  of  maples, 
other  trees  might  be  weed  trees. 

411.  The  plants  commonly  known  as 
weeds  have  the  power  to  distribute  them- 
selves   and    to    persist,  otherwise    they 

P  (241) 


40S.    Common    white 
pigweed.  —C  li  eno« 


podium   lilbt 


242 


WEEDS 


would  not  be  successful  competitors  or  vagrants.  Usually 
they  are  (1)  suited  to  a  wide  range  of  conditions;  (2)  strongly 
tenacious  of  life;  (3)  have  effective  means  of  dissemination; 
(4)  and  they  often  have  a  life-cycle  similar  to  that  of  some 
cultivated  plant,  and  they  therefore  take  the  fortunes  of  that 
plant.  As  examples  of  these  categories,  we  may  recall  the 
wide  range  of  such  plants  as  pigweeds  (Fig.  408)  and  docks; 
the  tenacity  and  endurance  of  Canada  thistles  (Fig.  409) 
and  quack-grass  (Fig.  27);  the  way  in  which  the  burdock 
spreads  its  seeds; 
the  fact  that  cockle 
(Fig.  181)  ripens 
with  the  wheat,  and 

the    seeds     pass  f    /  ^S 

through  the  separa-        >r^H/  /*$ 

tor  with  the  grain. 


Camilla  thistle. 


410.   Wild  carrot. 


411.  Redroot  pigweed. 
— Amarantus. 


412.  Certain  kinds  of  weeds  follow  certain  crops  or 
certain  systems  of  farming.  Dandelion  (Figs.  8,  302),  wild 
carrot  (Figs.  194,  410)  and  whiteweed  or  daisy  (Fig.  189) 
are  essentially  weeds  of  grass  lands;  purslane,  pigweed, 
chickweed,  redroot  (Figs.  406,  407,  411),  shepherd's  purse, 
are  pests  of  gardens  and  tilled  grounds;  cockle,  chess  (Fig. 


KINDS    OF    WEEDS 


243 


412),  kinghead  (an  ambrosia),  mustard  or  charlock  (Fig.  413) 
are  weeds  of  grain  crops;  dock,  plantain,  hound's-tongue, 
burdock  and  catnip  (Fig.  414)  are  weeds  of  back  yards  and 
by-ways;  sorrel,  mullein,  evening  prim- 
rose (Figs.  276,  415)  are  denizens  of  old 
fields;  ragweed  (Fig.  416),  mayweed 
(417),  stick-tight  (Fig.  418),  prickly 
lettuce  (Fig.  86),  sweet  clover  (Fig. 
184)  and  Russian  thistle  (Fig.  113)  are 
suited  to  roadsides  and  waste  places. 


412.  Chess  or  cheat. 


413.  Charlock,  a  weed  of 

grain  fields  and  open  414.  Catnip,  often  a  weed 

places.  about  old  places. 


413.  Some  weeds  come  and  go  year  by  year;  these  are 
mostly  weeds  of  tilled  and  raw  ground,  and  usually  annuals, 
as  pigweeds  of  several  kinds,  pepper-grass,  purslane,  rag- 
weed, pigeon-grass,  jimson  weed  (Fig.  275).  Such  weeds  are 
avoided  by  the  use  of  clean  seed,  preventing  the  weeds  from 
ripening  seeds,  and  taking  care  not  to  spread  them  in  manure. 

414.  Some  weeds  have  a  two-year  cycle,  making  a  tuft 
or  getting  a  foothold  one  year  and  ripening  seed  the  follow- 
ing year.  These  are  biennials,  as  mullein,  burdock,  bull 
thistle  (Fig.  254),  evening  primrose,  wild  carrot,  creeping 


244 


WEEDS 


mallow  or  "cheeses"  (Figs.  153,  149),  teasel.  These  weeds 
may  be  mown  when  coming  into  bloom,  or  the  plant  may  be 
spudded  or  cut  off  below  the  crown  in  fall, 
and  care  should  be  taken  not  to  spread  the 
seeds. 

415.  Some  weeds  persist  for  a  longer 
period,  sometimes  for  many  years.  These 
are  perennials,  as  docks  and  daisy.  Many 
of  them  propagate  by  underground  parts  as 
well  as  by  seeds,  such  as  quack-grass,  toad- 
flax (Fig.  227),  Canada  thistle,  Johnson- 
grass,  nut-grass  or  coco-grass,  bindweed, 
hawkweed  or  paint-brush.  In  lawns  and 
gardens,  the  roots  may  be  dug  out,  or  the 
plant  cut  below  the  ground  with  a  spud;  small 
patches  or  clumps  may  be  smothered  out  by 
covering  deeply  with  leaves  or  straw,  or 
sometimes  crowded  out  by  securing  a  dense  415.  Evening  prim- 
sod  on  the  area.   Thorough  and  clean  cultiva-       rose  in  frmt' 

I  tion    will    destroy    most 

kinds,  but  care  should  be 
taken  not  to  carry  the 
rootstocks  to  fresh  ground 
on  the  plow  or  cultivator. 
Meadow  and  pasture  seeds 
are  liable  to  be  carried  with 
grass  seed  and  with  grain. 
416.  The  best  treat- 
ment for  weeds  is  to  pre- 
vent or  change  the  condi- 
tions under  which  they 
thrive.  A  good  rotation  of 
crops,  cleaning  up  of  waste 
places  and  putting  them 
into  crops  or  sod  or  tim- 


i  Mi 


419.  Poisonous  mushroom. 


420.   Poisonous  mushroom 


(245) 


246 


WEEDS 


ber,  clean  tillage,  are  essential  to  a  clean,  weedless  farm.  To 
these  efforts  should  be  added  care  to  secure  clean  seed,  and 
manure  that  is  not  weed-in- 
fested; and  the  farmer  or  gar- 
dener should  be  alert  to  recog- 
nize new  weeds  as  soon  as  they 
invade  the  neighborhood  and 
be  prepared  to  meet  them. 

417.  On  lawns,  weeds  may 
be  lessened  by  the  use  of  the 
cleanest  grass  seed,  and  of  chem- 
ical fertilizers  or  only  well- 
rotted    or  other  clean   manure. 

The  grass  Seed  Should  be  SOWn      421.  Poison  ivy.-Rhus  Toxicodendron. 

very  thick  (3  to  5  bus.  of  blue  grass  to  the  acre)  both  to 
secure  a  soft  dense  lawn  and  to  crowd  out. weeds.  Frequent 
mowing  will  destroy  most  an- 
nual weeds,  and  these  weeds 
are  usually  most  troublesome 
when  the  lawn  is  newly  made. 
Dandelions  and  other  peren- 
nials may  be  taken  out  with  a 
spud  or  long,  strong  knife.  In 
badly  infested  places,  the  area 
may  need  to  be  dug  over,  and  a 
new  seeding  made  with  clean 
seed  and  chemical  fertilizer. 

418.  Some  weeds  may  be 
killed  by  poisons  or  herbicides. 
Sulfuric  acid  is  sometimes 
poured  on  the  crowns  of  plants 
in  lawns.  Salt  is  often  used  to 
kill  grass  and  weeds  in  gutters 
and  walks;  carbolic  acid  and  arsenical  poisons  are  some- 
times used  for  the  same  purpose.    Recipes  are  to  be  found 


422.  Poison  sumac,  poison  elder,  a 
bush  of  swamps  and  low  places. 
— Rhus  venenata  or  R.  Vernix. 


POISONOUS    PLANTS 


247 


423.  Poison  oak,  a  trailing  or  climbing 
plant  of  the  Pacific  Coast. — Rhus 
diversiloba. 


in  books  and  government  publications,  and  periodicals. 
Sprays  of  copper  sulfate  or  iron  sulfate  are  sometimes  used 
for  mustard  and  other  field 
weeds.  A  3  per  cent  solution 
of  copper  sulfate  (about  10  lb. 
to  40  gal.  water)  at  the  rate  of 
40  to  50  gallons  an  acre  de- 
stroys wild  mustard  without 
injuring  peas  or  cereals  with 
which  the  weed  may  be  grow- 
ing. There  are  special  herbi- 
cides about  which  information 
can  be  secured  from  the  ex- 
periment stations.  These  her- 
bicides are  poisonous,  and 
must  be  used  with  caution  and 
only  by  those  who  are  reliable  and  who  understand  them. 

419.  Poisonous  Plants. — Many  plants  produce  ill  effects 
on  live  stock  and  human  beings 
when  eaten;  and  some  are  in- 
jurious to  the  touch.  Some 
plants  produce  such  marked 
results,  leading  even  to  death, 
that  they  are  known  as  poison- 
ous plants.  Some  of  the  mush- 
rooms are  examples,  two  of  which 
are  shown  in  the  illustrations 
(Figs.  419,  420),  (wild  mush- 
rooms should  never  be  eaten  ex- 
cept on  the  advice  of  someone 
who  knows  the  different  species). 
Many  plants  of  the  parsley 
family  (Umbellifcrae)  are  poison- 
ous; the  poison  hemlock  and  the  water  hemlock  or  mus- 
quash-root are  deadly  when  eaten.    The  poison  ivy  is  shown 


424.  Solanum  Dulcamara. 


248 


in  Fig.  421,  poison  sumac  in  Fig.  422,  and  poison  oak  of  the 
Pacific  coast  in  Fig.  423;  these  are  poisonous  to  the  touch. 
The  handsome  red  berries  of  the  bittersweet 
(Solanum  Dulcamara,  Fig.  424)  are  poisonous 
if  eaten;  and  it  has  poisonous  relatives. 

Review. — Explain  your  understanding  of  a  weed. 
How  may  we  classify  weeds?  What  are  the  com- 
monest kinds  of  weeds  in  your  locality?  What  enables  a  plant  to  be  an 
habitual  weed?  Name  some  of  the  weed  groups  or  associations.  Name 
the  ways  in  which  weeds  may  be  controlled  or  eradicated  on  farms.  On 
lawns.  What  would  you  recommend  to  be  done  with  weedy  roadsides? 
Are  there  laws  in  your  state  for  the  control  of  weeds?  Are  there 
village  or  city  ordinances  on  the  subject  where  you  live?  What  is 
an  herbicide?  Name  the  poisonous  plants  that  you  know,  or  of  which 
you  have  heard. 

Note. — Every  class  studying  plants  should  learn  the  usual  weeds 
of  the  neighborhood,  and  should  make  herbarium  specimens  of  them. 
Discussions  should  be  had  of  the  weeds  infesting  the  local  crops,  and 
the  reasons  for  them.  The  school  should  have  a  collection  of  weed 
seeds  in  bottles,  and  it  should  study  commercial  samples  of  grain  and 
grass  seeds.  The  U.  S.  Department  of  Agriculture  and  perhaps  the 
State  Experiment  Station  may  have  bulletins  to  aid  in  such  examina- 
tion. If  the  school  is  to  indentify  weed  seeds  in  such  samples,  it  should 
also  have  a  collection  in  bottles  of  the  leading  grains,  grass  seeds  and 
field  seeds.  A  small  lens  or  magnifier  is  needed  for  this  examination,  as 
shown  in  Fig.  425,  or  in  Figs.  214,  216. 

Many  plants  are  poisonous  to  a  greater  or  less  degree.  No  one  should 
eat  of  any  plant  or  fruit  or  root  that  he  does  not  know  to  be  safe. 
Some  plant  families  are  known  for  poisonous  qualities:  as  Solanacese,  of 
which  the  common  black  nightshade  (Solanum  nigrum)  and  others  are 
examples;  Umbelliferse,  with  the  hemlock  herbs,  water  parsnip,  and 
others;  Ranunculacea?,  with  the  aconites  or  monkshoods;  and  other 
families.  Fatalities  are  frequently  reported  from  eating  the  thick  roots 
of  certain  Umbelliferse.  There  are  useful  government  publications  on 
poisonous  plants. 


CHAPTER   XXXIV 


CROPS 

420.  Plants  that  arc  grown  by  man  for  his  uses  constitute 
a  crop.  The  term  is  commonly  used  for  the  product  of  a 
field,  but  is  just  as  applicable  to  the  product  of  a  planted  or 
managed  forest  or  of  a  garden  or  a  greenhouse.  Thus  we  may 
speak  of  a  crop  of  wheat,  of  rye,  of  hemp,  of  pine  timber,  of 
celery,  of  roses 
or  violets,  of 
mushrooms. 

421.  Crops 
may  be  distin- 
guished into  four 
groups: (1)  those 
grown  for  hum  an 
food  or  medicine 
or  condiments, 
as  rice,  potatoes, 
strawberries;  (2) 
those  grown  to 
provide  materials 
for  .shelter  and 
clothing,  and  for 
use  in  the  manu- 
facturing arts,  as 

timber        Ontton  4^6'  Two  crops  growing  together — outs  and  peas  for  forage. 

flax,  rubber;  (3)  those  grown  to  satisfy  the  artistic  impulses, 
as  roses;  (4)  those  grown  for  food  of  domestic  animals,  as  grass 
and  clover.  Another  division,  and  one  followed  in  a  general 
way  in  colleges  of  agriculture,  is  into  field  crops  and  horti- 
(249) 


wXSKi 


250 


CROPS 


cultural  crops;  and  the  horticultural  crops  include  fruit  crops 
(pomology),  vegetable-gardening  crops  (vegetable-gardening 
or  olericulture) ,  flower-  and  ornament-crops  (floriculture) . 

422.  We  may  group  crops  also  as  follows  into  more  par- 
ticular divisions:  forage  and  fodder  crops;  cereal  grains; 
root-crops;  fiber-crops;  sugar  plants;  oil  plants;  dye-stuff 

plants;  bever- 
age-producing 
plants ;  s  t  i  m  u  - 
lants;  aromatic 
and  medicinal 
plants;  perfum- 
ery plants;  fruit 
crops;  vegetable- 
garden  crops; 
timber  crops; 
manuring  crops. 
Some  crops  fall 
under  more  than 
one  division,  de- 
pending on  the 
purposes  for 
which  they  are 
grown,  as  oats, 
beets,  peas,  sor- 
ghum, maize  or  Indian  corn,  flax:  explain  why.  Sometimes 
two  plants  are  grown  together  purposely,  as  shown  in  Fig. 
426,  and  also  in  Fig.  427. 

423.  Many  of  the  crops  may  be  assembled,  on  the  basis 
of  their  botanical  affinities,  into  the  families  to  which  they 
belong:  Grass-family  crops,  all  cereal  grains  as  well  as  the 
meadow  and  pasture  grasses,  as  wheat  (Fig.  384),  rye,  barley, 
oats  (Fig.  382),  rice,  maize  (Fig.  427),  sorghum  (Fig.  20),  kafir, 
broom-corn  (Fig.  429),  millets  of  several  kinds,  sugar-cane 
(Fig.  428);  leguminous  or  pulse  crops,  beans  and  peas  of  all 


427.  A  crop  of  Indian  Corn. 


THE   MANY   KINDS   OF   CROPS 


251 


kinds,  cowpea,  peanut  or  goober,  alfalfa,  clovers,  sweet 
clover,  lespedeza,  vetch;  cruciferous  or  mustard-family  crops, 
mustard,  cabbage,  kale,  rape,  turnip,  rutabaga,  kohlrabi ;  rose- 
family  crops,  rose,  apple,  pear,  plum,  peach,  almond,  apricot, 
cherry,  quince,  strawberry,  blackberry,  raspberry  medlar, 
loquat;  cucurbitous 
crops,  pumpkin, 
squash,  melon,  water- 
melon,  cucumber, 
gherkin,  gourds; 
solanaceous  crops, 
potato,  tomato,  to- 
bacco. Some  of  the 
important  crops  be- 
long to  families  that 
do  not  yield  other 
leading  cultivated 
species,  as  buck- 
wheat to  the  knot- 
weed  family,  cotton 
to  the  mallow  family, 
flax  to  the  flax  family, 
hemp  and  hops  to 
the  nettle  family, 
sugar-beet  and  other 
beets  to  the  goose- 
foot  family. 

424.  How  to  Study  a  Crop. — Every  botany  class  should 
know  the  leading  crops  of  its  vicinity  and  region,  including 
the  grasses,  the  grains,  the  most  important  fruits  and  vege- 
tables, and  any  special  crops  that  may  be  grown  in  the  locality. 
This  knowledge  may  be  derived  from  the  experience  of  the 
members  of  the  class,  from  inquiries  made  of  farmers  and 
from  census  figures.  Having  learned  the  kinds  of  crops  and 
their  relative  importance  in  the  region,   the  class  should 


428.  A  crop  of  sugar-ca 


252  crops 

try  to  determine  why  they  are  important  there,  and  should 
then  gather  information  as  to  their  importance  in  other 
regions  and  where  they  are  grown  with  the  greatest  success. 
Then  may  follow  such  details  as  the  rotation  or  farm-plan 
in  which  these  crops  find  a  place,  the  times  and  methods  of 
sowing,  the  fertilizers  used,  the  methods  of  tilling,  harvest- 
ing and  marketing;  and  then  inquire  as  to  any  special 
difficulties  in  the  way  of  insects  or  plant  diseases.    The  cost 


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429.   A  crop  of  broom-corn. 

of  growing  the  crop,  the  usual  prices  and  the  yields  should 
always  be  determined  as  nearly  as  possible. 

425.  How  to  Study  a  Crop  Plant. — We  have  been  directed 
in  this  book  to  some  of  the  important  things  to  look  for  in  a 
plant,  from  root  to  fruit;  and  our  attention  has  been  called 
to  some  of  the  relations  of  plants  when  they  live  together. 
These  observations  may  be  made  on  cultivated  plants 
with  as  much  interest  as  on  wild  plants.  The  cultivator  of 
plants  should  develop  the  habit  of  careful  observation  on 
individual  plants  that  he  cultivates;  this  observation  should 
aid  him  in  discovering  the  reasons  for  failure  or  success  in 
the  growing  of  plants.   The  student  should  go  directly  to  the 


THE    FLANT   THAT   MAKES    THE    CROP 


253 


plant.    Examine  the  plant  where  it  stands, — height,  spread, 
color,  mode  of  branching  and  any  special  peculiarities:  make 


$ 


430.   Harvesting  a  peanut  crop. 

a  sketch.  Collect  the  plant,  root  and  all,- — character  of  root 
as  to  depth  and  spread,  mode  of  branching,  nodules  (if  a 
legume),  and  other  features:  make  sketch.  The  specimen 
may  now  be  taken  to  the  schoolroom  or  other  laboratory, 
and  studied  as  to  direction  and  size  of  stem,  features  of 
nodes,  character  of  bark  or  rind,  position  of  branches  and 
leaves  and  flowers,  characters  of  leaves  and  flowers  and  fruits, 
how  pollinated,  yield,  whether  it  bears  any  evidence  of  dis- 
ease or  insect  injury  or  lack  of  normal  vigor,  whether  it 
has  suffered  in  contest  with  its  fellows  or  with  other  plants: 
make  notes  and  sketches. 

426.  Plants  or  plant  products  are  sometimes  judged  by 
comparing  them 
with  an  assumed 
or  ideal  standard 
of  perfection. 
These  standards 
may  be  printed  in 
form  for  ready 
use,  and  they  are 
then     known     as  ji.  A  crop*  of  winery  trees.  Yew-old  peach  trees. 


254 


CROPS 


score-cards.    A  few  useful  score-cards  of  common  cultivated 
plants  are  as  follows: 


Plum. 
Form. 
Size.. 
Color. 


Points 

..  10 
..  25 
..    15 


Uniformity  of  fruits 25 

Freedom  from  blemish 25 

100 
Apple. 

Size 10 

Color 20 

Good  shape  or  form 10 

Uniformity 15 

Freedom  from  blemish 20 

Texture  and  flavor 25 

100 
Sweet  Pea. 

Length  of  stem 25 

Color 20 

Size 25 

Substance 15 

Number  of  flowers  on  stem .    15 

100 
Wheat  (grain). 

Trueness  to  variety 10 

Uniformity  in  size  and  shape 

of  kernel 10 

Color  of  grain 10 

Freedom  from  mixture 15 

Size  of  kernel 10 

Percentage  and  nature  of  im- 
purities (weed  seed,  dirt).  15 
Percentage     of     damaged, 

smutty  or  musty  kernels  .  5 

Weight  of  grain  per  bus ....  10 

Germination  test 15 


Potato.  Points 

Uniformity  of  sample 20 

Symmetry  of  tubers 15 

Trueness  to  type 20 

Freedom  from  disease  and 

insects 15 

Commercial  value 30 

100 
Corn. 

Adaptability  to  purpose ....   25 
Seed  condition,  as  to  whether 

fresh,  well  kept,  etc 15 

Shape  of  kernel 15 

Uniformity  and  trueness  to 

type 15 

Weight  of  ear 10 

Length    and    proportion    of 

ear 10 

Color  of  grain  and  cob 5 

Butts  and  tips  covered 5 

100 

Determine    in    advance    what 

weight  and  proportion  of  ear  is  to 

be  assumed  for  the  variety  under 

examination. 


Carnation. 
Color.  .  . 

Size 

Calyx. . . 
Stem . . . 


25 

20 

5 

20 

Substance     or     texture    of 

flower 10 

Form 15 

Fragrance 5 


100 


100 


FESTIVALS   AND    EXCURSION^  255 

The  "points"  in  the  score-card  represent  the  mark  of 
perfection:  if  the  size  of  the  carnation  flower  is  normal  for 
the  variety  under  examination,  the  particular  specimen  will 
be  marked  20;  if  it  should  receive  a  rating  of  onlyt75  per 
cent  perfect,  it  receives  15  points.  In  any  large  bunch  of 
carnations,  one  plant  may  be  taken  to  represent  perfection 
in  one  feature  and  another  plant  for  another  feature;  or, 
better,  if  an  expert  carnation-grower  is  available  he  may  set 
the  ideal  of  perfection.  The  pupil  may  make  up  his  own 
ideal  as  to  what  the  perfect  plant  or  product  should  be. 

427.  The  Vegetation  Environment. — The  botany  class 
should  take  part  in  a  harvest  festival,  in  which  the  plant 
products  of  the  community  are  exhibited,  together  with  the 
wild  plants  in  the  form  of  leaves,  flowers,  nuts  and  other 
interesting  parts.  Members  of  the  class  should  explain 
what  the  products  and  the  plants  mean. 

428.  The  class  should  also  know  the  most  important 
vegetation  of  the  vicinity,  and  should  arrange  excursions  for 
the  school  or  classroom  to  close-by  places  in  order  to  ex- 
plain the  vegetation  setting  of  the  school;  and  if  possible  a 
crop  excursion  for  the  entire  school  should  be  undertaken. 

Review. — What  is  a  crop?  Name  the  six  most  important  crops 
of  your  neighborhood.  How  may  crops  be  classified  or  grouped?  Give 
two  examples  in  each  group.  What  natural  families  contribute  very 
important  crops  in  temperate  regions?  Outline  a  study  blank  for  the 
general  study  of  the  most  important  crop  in  the  locality.  Make  a 
similar  outline  for  a  study  of  the  plant  itself.  What  is  a  score-card 
and  how  it  is  used?   What  may  an  exhibition  teach?   An  excursion? 

Note. — Various  texts  and  bulletins  now  set  forth  the  standards 
of  perfection  in  many  of  the  leading  crop  products,  and  give  the  student 
definite  statements  of  what  is  considered  to  be  the  product  that  should 
score  100. 


CHAPTER  XXXV 

THE   FOREST 

429.  An  area  of  trees  growing  close  together  and  having 
its  own  features  and  its  own  life  is  a  forest.  An  avenue  of 
trees,  or  a  grove  of  shade  trees,  is  not  a  forest.  The  science 
and  the  practice  of  growing  and  utilizing  forests  is  forestry. 
A  forest  is  a  great  plant  society. 

430.  Forest   trees  constitute  a  crop.     The  chief  product 


is  timber;  other  products  are  stove-wood, 


bark,  resin,  tur- 
pentine, rubber, 
paper  pulp.  The 
crop  is  regularly 
harvested,  in 
some  cases  by 
removing  the 
entire  forest  and 
planting  anew, 
but  often,  in 
planted      and 


I 

Wr/K'  T^l*~i      managed  forests, 
HV^yfcLU'.'/Y'vi     by     removing 


432.  A  stand  of  younj 


g 

the    mature    or 
ripe  trees  and  allowing  the  forest  to  continue. 

431.  The  value  of  the  forest  crop  depends  on  the  kinds 
of  trees,  how  they  are  mixed  or  associated  in  the  forest,  and 
the  distance  at  which  they  stand  apart,  as  well  as  on  location 
and  soil  and  climate,  freedom  from  insects  and  timber  dis- 
eases, and  other  factors.  A  natural  forest  may  not  be  the 
most  productive  forest,  any  more  than  a  natural  or  wild 
meadow  may  be  a  perfect  meadow.  There  are  likely  to  be 
(256) 


SILVICULTURE    AND    ARBORICULTURE 


257 


open  and  poor  spots,  and  many  of  the  trees  may  be  weed 
trees  of  no  value  in  themselves  and  interfering  with  the 
growth  of  useful  trees.  Some  natural  forests  (as  that  shown 
in  Fig.  388)  present  a  uniform  and  continuous  stand  of 
timber  of  one  kind;  others  (as  in  Fig.  387)  are  mixed  forests. 
Both  kinds  may  be  useful  and  desirable. 

432.  Trees  standing  alone  or  on  the  edge  of  a  forest  do  not 
produce  good  timber  because  they  branch  too  low  and  are 
likely   to   be   too   much   exposed   to   wind.     They   produce 


short  and  knotty 
forest  be  thickly 
and      continu- 
ously planted. 

433.  Forests 
may  be  planted 
anew;  or  nat- 
ural forests  may 
be  perpetuated 
by  removal  of 
ripe  and  unde- 
sirable trees  and 
the  in-planting 
or  saving  of 
other  trees.  The 


logs.   (Fig.  400.)   It  is  essential  that  the 


433.  A  stand  of  young  timber  after  moderate  thinning. 


planting  and  rearing  of  trees  in  forests  is  silviculture.  The 
planting  and  rearing  of  trees  in  general  is  arboriculture, 
and  this  may  have  no  direct  relation  to  forestry,  because  the 
planting  may  be  of  lawn  trees,  park  trees,  roadside  trees  or 
fruit  trees.  Silviculture  is  one  part  of  forestry;  other  parts 
or  divisions  are  forest  management,  harvesting,  marketing, 
timber  technology.  The  safeguarding  and  utilization  of  the 
forests,  both  on  public  and  private  lands,  is  one  of  the  great 
public  questions,  and  demands  the  attention  of  persons  of 
special  training  and  skill. 

434.  Forestry  is  an  important  farming  question,  for  the 


258 


THE     FOREST 


forest  crop  may  be  as  important  as  other  crops  on  the  farm. 
In  hilly  regions,  practically  all  farms  have  forests,  yielding 
timber,  posts,  firewood  and  other  supplies,  and  protect- 
ing lands  from  washing,  affording  windbreaks,  and  providing 
good  use  for  lands  that  cannot  be  profitably  devoted  to 
other  crops. 
There  are  many 
planted  wood- 
lots  in  the  West. 
The  manage- 
ment of  these 
small  forests  is 
called  farm  for- 
estry. Every 
good  general 
farmer  should 
be  skillful  in 
the  growing  of 
forest  crops  as 
in  the  growing 
of  grain  crops 
or  fruit  crops. 
The  principles 
of  good  plant- 
growing  may  be 
applied  to  the 
forest,  the  trees 
being  planted, 
cared  for,  the  forest  thinned  if  too  thick  (Figs.  432,  433) 
or  rilled  if  too  thin,  fire  kept  out,  and  the  trees  properly 
harvested. 

435.  What  small  forests  contribute  to  the  farm,  the  larger 
public  forests  contribute  to  the  nation  or  to  all  the  people: 
profitable  utilization  of  remote,  rocky  and  less  fertile  areas;  the 
holding  back  of  the  rainfall  so  that  floods  and  serious  erosions 


434.  Absolute  forest  land, — unadaptable  to  other  uses. 


WHERE    FORESTS    MAY    BE    GROWN 


259 


435.  Absolute  forest  land, — a  cypress  swamp. 


are  prevented  and  the  flow  of  navigable  streams  regulated; 
protection  of  wild  life;  tempering  of  physical  conditions 
by  regulation 
of  water -flow  in 
streams  and  lakes 
and  elsewhere 
and  by  checking 
the  sweep  of 
winds;  providing 
an  attractive 
cover  for  large 
areas  of  the  sur- 
face of  the  earth, 
in  which  the 
people  may  find 
recreation  and 
help.  Areas  that 
can  be  utilized  for  no  other  crop  than  forest  are  said  to  be 
absolute  forest  land  (Figs.  434,  435) ;  and  much  land  that  is 
available  to  some  extent  for  pasture  or  other  croppage 
may  still   be  most  profitable  in  forests.     (Fig.  436.)    Very 

special    forests 


(Fig.  437)  may 
be  grown  on 
arable  lands. 
In  the  general 
scheme  or  plan 
of  a  farm,  a 
forest  or  wood- 
lot  may  be  an 
essential  part; 
and  likewise,  in 
a  national 
domain  large 
forest  areas  are 


_'■*&*  ~2*t 


436.  Land  that  may  be  profitably  used  for  forestry  purposes. 


260 


THE     FOREST 


essential.    Even  with  the  greater  use  of  cement,  the  demand 
for  timber  will  increase. 

Review. — What  is  a  forest?  Forestry?  In  what  sense  is  a  forest 
a  crop?  On  what  general  factors  does  the  value  of  a  forest  crop  depend? 
Name  some  of  the  forest  products.  How  may  man  produce  a  more 
profitable  forest  than  nature  often  does?  What  do  you  say  about  the 
timber  value  of  trees  standing  alone?  What  is  aboriculture?  Silvi- 
culture? Farm  forestry?  What  are  some  of  the  large  values  or  benefits 
of  forests?  What  is  the  nature  of  the  forests  in  your  neighborhood? 
What  kinds  of  trees  dominate  them? 


IT — r7"7|~y '  ry\^MlMj 


MkM 


W;m 


I  i  »  \1  HiW  i  i! \\m 


437.  A  forest  of  paper  bamboo. 


PART  III 

HISTOLOGY,    OR   THE  MINUTE 

STRUCTURE  OF  PLANTS 


CHAPTER  XXXVI 

THE    CELL 

436.  Plants  Composed  of  Cells. — All  the  higher  plants 
arc  made  up  of  a  large  number  of  small  structures  termed 
cells.  They  are  so  minute  that,  in  most  cases,  they  are 
invisible  to  the  naked  eye.  These  cells  are  box-like  structures. 
They  are  of  many  forms.  Many  of  the  lower  forms  of  plants, 
as  bacteria,  yeasts,  spores  of  fungi,  and  many  of  the  algae, 
are  composed  of  but  a  single  cell. 

437.  Cells  are  of  Many  Forms. — In  general,  plant  cells 
may  be  assigned  to  some  one  of  the  following  forms: 

Spherical,  as  in  protococcus  (a  minute  alga  to  be  found 
on  damp  walls  and  rocks),  and  apple  flesh; 

polyhedral,  or  many-sided,  as  in  pith  of  elder; 

tabular,  or  flat,  as  in  epidermis  of  leaves; 

cylindrical,  as  in  vaucheria,  spirogyra  (fresh  water  algae) ; 

fibrous,  as  cotton  fibers; 

vascular,  as  the  ducts  of  wood; 

stellate,  as  in  the  interior  of  leaves  of  lathyrus  (sweet 
pea)  and  other  plants. 

438.  Parts  of  a  Cell. — The  typical  cell  is  composed  of 
living  and  dead  matter.  The  living  matter  of  the  cell  is  the 
protoplasm.  The  protoplasm  is  differentiated  into  a  nucleus, 
cytoplasm  and  plastids. 

439.  The  nucleus  is  usually  a  round  or  elliptical  body, 
denser  than  the  remainder  of  the  protoplasm,  in  which  it  may 
be  imbedded  or  from  which  it  may  be  suspended  by  strands 
of  protoplasm  called  cytoplasm.  The  cytoplasm  lines  the  wall 
of  every  living  cell,  and  commonly  in  old  cells  the  nucleus 
is  in  this  layer  of  cytoplasm.    In  the  cell  may  be  aggregates 

(263) 


264 


THE     CELL 


of  protoplasm  forming  definite  structures,  usually  scattered 
in  the  layer  of  cytoplasm.  They  are  the  plastids.  The  ones 
most  familiar  are  the  chloroplasts,  in  which  the  green  pig- 
ment chlorophyll  is  imbedded.  They  are  found  in  cells  of 
leaves  and  stems  exposed  to  the  light.  Plastids  are  not  found 
in  all  cells.  The  dead  part  of  the  cell  is  the  cell-wall,  the  cell- 
sap  stored  in  chambers  or  pockets  in  the  protoplasm  called 
vacuoles  (Fig.  438),  and  various  inclusions.  The  cell-sap 
contains  mineral  nutrients  in  solution  or  suspension,  as  well 
as  organic  foods,  as  sugar  and  other  sub- 
stances. Imbedded  in  the  cytoplasm  or  in 
the  plastids  may  be  starch  grains,  oil 
droplets  and  other  substances.  In  the 
nucleus  is  a  densely  granular  body  called 
the  nucleolus. 

440.  Study  of  Cell. — Examine  with  the 
aid  of  the  microscope  the  cells  in  the  sta- 
men hair  of  tradescantia  or  spider-wort. 
(Fig.  438.)  If  the  flowers  of  this  plant  are 
not  available,  use  the  young  bristle  hairs 
of  squash  plants;  a  plant  a  few  weeks  old 
will  supply  sufficient  hairs.  Note  the  shape 
of  the  cell  and  the  contents.  The  nucleus 
will  probably  be  located  near  the  middle 
of  the  cell,  and  to  it  run  the  strands  of 
cytoplasm.  The  protoplasm  is  not  entirely 
homogeneous.  It  is  composed  of  a  viscous, 
colorless  fluid  in  which  are  imbedded  many 
minute  granules.  In  a  young  cell  the  pro- 
toplasm fills  almost  the  entire  cell.  In  an 
old  cell  the  vacuoles  are  of  increased  size. 
.  Compare  old  and  young  cells  in  the  stamen 
topiasm  in  a  cell  of  a    hairs  of  tradescantia  or  in  squash  hairs  for 

stamen  hair  of  trade-  .  .  .  , 

scantia   or   spider-    their  protoplasmic  content.    Examine  the 
^Magnified eoo    cells  of  the  epidermis  of  the  onion.    Note 


PROTOPLASM  265 

the  large  volume  of  the  cell  occupied  by  the  vacuoles.  The 
protoplasm  in  this  case  will  consist  probably  only  of  the 
lining  layer  of  cytoplasm  in  which  the  nucleus  is  imbedded. 
Examine  the  leaf  of  the  water  plant  elodea  or  the  thin 
leaves  of  some  of  the  mosses.  Note  the  character  of  chloro- 
plasts  in  the  cells  (Fig.  439).  These  chloroplasts  may 
be  observed  in  the  cells  of  the  leaf  of  higher  plants  if  a 
cross-section  of  the  leaf  is  cut  and  a  microscopical  examina- 
tion made.  Study  should  be  made  of  cells  of  the  soft  pulp  of 
a  celery  stem;  of  hairs  scraped  from  the  surface  of  a  begonia 
leaf;  of  threads  of  spirogyra;  soft,  white  cells  of  apple;  the 


a^  <gg>  -g  <a  §  <s:  te  ga^^s; 


7 

439.   Rotation  of  protoplasm  in  Elodea  canadensis  (often  known  as 
Anacharis).    Common  in  ponds. 

cells  of  the  potato  tuber  (observe  the  starch  grains).  Ex- 
amine the  lower  epidermal  cells  of  cyclamen,  irises,  or  coleus 
and  note  that  the  cell-sap  is  colored  by  a  red  pigment. 
The  beet  also  has  cells  with  red  pigmented  cell-sap. 

441.  Nature  of  Protoplasm. — The  living  substance  is 
protoplasm.  It  is  proteid.  Its  chemical  composition  is  not 
known.  It  is  semi-liquid,  of  hyaline  color,  and  colloidal  in 
nature.  It  may  be  killed  by  heating  to  a  high  temperature 
or  by  various  chemical  reagents.  The  whole  principle  of 
antiseptics  is  based  on  these  facts  and  processes. 

442.  Within  the  cell-wall,  at  times  the  protoplasm 
shows  a  tendency  to  move  from  place  to  place.  This  move- 
ment is  chiefly  of  two  kinds:  (1)  Circulation,  or  movement 
not  only  along  the  walls  but  also  across  the  cell-body,  as  seen 
in  the  long,  thin-walled  cells  of  celandine;  in  the  staminal 
hairs  of  tradescantia  (Fig.  438);  in  the  bristles  of  squash 
vines;  in  the  stinging  hairs  of  nettle;  in  stellate  hairs  of  holly- 
hock.   (2)  Rotation,  or  movement  along  the  walls  only,  well 


266  THE     CELL 

seen  in  the  cells  of  many  water  plants,  as  elodea  (Fig.  439), 
chara,  and  nitella. 

443.  Besides  these  and  other  movements  of  protoplasm 
within  the  cell-wall,  there  are  also  movements  of  naked 
protoplasm,  of  two  main  types:  (1)  Amoeboid  or  creeping 
movements,  such  as  may  be  seen  in  a  plasmodium  of  myxomy- 
cetes,  or  in  an  amoeba.  (2)  Swimming  by  means  of  cilia  or 
flagella,  illustrated  in  the  swarm-spores  of  water  fungi,  and 
of  some  algse.  By  the  latter  type  of  movement  the  unicellular 
bodies  (swarm-spores)  are  often  moved  very  rapidly.  To 
see  movement  in  protoplasm,  carefully  mount  in  water  a 
few  hairs  from  the  stamens  of  tradescantia  (spider-wort). 
The  water  should  not  be  too  cold.  Examine  with  a  power 
high  enough  to  see  the  granules  of  protoplasm.  Make  a 
sketch  of  several  cells  and  their  contents.  It  may  be  neces- 
sary to  make  several  trials  before  success  is  attained  in 
this  experiment.  If  the  microscope  is  cold,  heat  the  stage 
gently  with  an  alcohol  lamp,  or  by  other  means;  or  warm 
the  room.    See  Fig.  438. 

444.  Nature  of  Cell-wall. — The  cell-wall  of  very  young 
cells  is  a  delicate  film  or  membrane.  As  a  cell  grows  in 
size  the  wall  remains  thin  and  does  not  begin  to  thicken 
until  the  cell  has  ceased  to  enlarge.  The  fundamental  sub- 
stance of   cell-walls  is  a  carbohydrate  known  as  cellulose. 

The    cellulose    usually    stains     blue    with 
I     hematoxylin.    Often  by  incrustations  or  de- 
posits of  one  kind  or  another,  the  cellulose 
reaction  is  lost  or  obscured.     Two  of  the 
most  common  additions  are  lignin,  forming 
440.  Bordered  pits  in    wood,  and  suberin,  forming  cork.  The  walls 
pine  wood.  then  are  gaid  tQ  be  lignified  or  suberized. 

445.  In  all  the  cells  studied  in  the  above  experiments, 
the  walls  are  thin  and  soft.  In  general,  those  cells  that 
have  thin  walls  are  called  parenchymatous  cells.  Some 
cells,  as  those  of  nuts  and  the  grit  of  pear  fruit,  have  very 


CELL-WALLS 


267 


an 

SO 

s 

c  5 

s 

^ 

I 

^ 

55 

^ 

s 

3 

^ 

^ 

-  „M 

441.  Markings  in  cell- 
walls,  sp,  spiral;  an, 
annular;  sc,  scalari- 
form. 


thick  walls,  and  are  called  sclerenchymatous  cells.  In  many 
cases  the  cell-walls  are  intermediate  between  these  extremes. 
446.  Cell-walls  often  thicken  by  additions  to  their 
inner  surface.  This  increase  in  thickness  seldom  takes 
place  uniformly  in  all  parts.  Many  times  the  wall  remains 
thin  at  certain  places,  while  the  most  of  the  wall  becomes 
very  thick.  Again  the  walls  may  thicken 
very  much  in  angles  or  along  certain 
lines,  while  most  of  the  wall  remains 
thin.  As  a  result  of  this  uneven  thicken- 
ing, the  walls  of  cells  take  on  certain 
definite  markings.  Some  of  the  names 
applied  to  these  markings  are: 

Pitted,    with    little    holes    or   depres- 
sions, forming  very  thin  places,  as 
seen  in  seeds  of  sunflower,  and  in  the  large  vessels  in 
the  stem  of  the  cucumber. 
Bordered  pits,  when  the  pits  are  inclosed  in  the  cell-wall, 

as  in  wood  of  pines  and  other  conifers.    (Fig.  440.) 
Spiral,  with  the  thickening  in  a  spiral  band,  as  in  the 
primary  wood  of  most  woody  plants  and  in  the  veins  of 
leaves.    (Fig.  441.) 
Annular,   with   thickening   in   the   form   of   rings;   seen 

in  the  small  vessels 

of    the   bundles    in 

stem  of  Indian  corn. 

(Fig.  441.) 

Scalariform,    with 

elongated     thin 

places   in  the  wall, 

alternating  with  the 

thick   ridges   which 

appear  like  the  rounds  of  a  ladder.    (Fig.   441.)    These 

are  well  shown  in  a  longitudinal  section  of  the  root  of 

the  brake  fern  (Pteris). 


442.  Four  steps  in  process  of  cell-*li 
cell  at  left,  fai  advanced  in  div 
cells  at  right. 


268 


THE     CELL 


447.  While  a  true  cell  must  have  cytoplasm  and  a  nucleus, 
the  word  cell  is  applied  to  the  unit  structures  that  make  up 
the  plant  body.  Many  of  these  cells  are  dead.  The  wood  of 
trees  consists  largely  of  dead  wood.  The  pith  of  stems  also 
may  consist  largely  of  dead  cells.  The  cells  of  bark  are  largely 
dead  cells. 

448.  Multiplication  of  Cells. — Every  cell  owes  its  origin 
to  some  previous  cell,  and  all  go  back  eventually  to  the  germ- 


443.  Nuclear  and  cell  division  in  the  root  of  corn:  cell  with  prominent  resting  nucleus 
(a):  prophases  of  nuclear  division,  spirem  (6)  and  chromosome  (c)  stages;  bipolar 
spindle  (d)  ;  early  (e)  and  late  (/)  anaphases;  telophases  ig)  and  first  evidence 
of  cell-plate;  location  of  cell-wall  clearly  defined  (h).    (After  Curtis.) 

cells.  The  method  whereby  cells  are  produced  is  complex. 
The  process  is  at  first  internal,  and  consists  in  the  formation 
of  definite  aggregates  of  protoplasm  derived  from  the  nucleus, 
called  chromosomes.  In  the  course  of  the  formation  of  these 
chromosomes,  intricate  changes  occur  in  the  cell  nucleus 


CELL    DIVISION  269 

and  cytoplasm.  In  the  division  of  the  cell,  equal  numbers 
of  these  chromosomes  are  found  at  its  equator.  Half  of  these 
chromosomes  then  go  to  the  opposite  poles  of  the  cell  and 
unite  again  to  form  at  each  pole  a  nucleus.  A  cell-wall  is 
then  laid  down  at  the  equator,  and  we  have  two  cells  in  the 
place  of  one.  Enlargement  and  further  changes  may  go  on 
in  these  two  cells.  The  method  of  cell  division  by  this  complex 
means  is  known  as  mitosis  or  karyokinesis.  It  is  exceedingly 
complex  and  too  difficult  for  the  beginner  to  follow  or  to 
comprehend.  Some  of  the  stages  are  given  in  Fig.  442.  A 
more  detailed  representation  of  these  changes  is  shown  in 
Fig.  443. 

Review. — Of  what  is  the  plant  composed?  What  is  the  general 
nature  of  cells?  Forms  of  cells?  What  part  of  the  cell  is  dead  matter? 
Living  matter?  Compare  different  cells  studied.  State  your  conception 
of  protoplasm.  State  the  divisions  in  the  protoplasm.  Name  two  kinds 
of  movement  of  protoplasm.  What  is  the  nature  of  the  cell- wall?  Its 
modifications?   How  do  cells  multiply? 


CHAPTER  XXXVII 

CONTENTS  AND  PRODUCTS  OF  CELLS 

449.  The  Living  Cell  is  a  Laboratory. — In  nearly  all 
cells  are  found  one  or  more  non-protoplasmic  substances 
produced  by  the  plant.  Some  of  these  are  very  useful  to 
the  plant,  and  others  seem  to  be  waste  or  by-products.  There 
is  considerable  division  of  labor  among  the  cells  of  higher 
plants,  one  cell  or  group  of  cells  producing  one  product,  and 
another  group  of  cells  producing  another  product  and  func- 
tioning in  a  different  way.  We  know  that  there  is  also 
division  of  labor  among  the  different  organs  of  a  plant. 

450.  Chlorophyll. — Cells  may  contain  chlorophyll  bodies 
if  they  are  exposed  to  the  sunlight.  Chlorophyll  is  a  green 
substance  infiltrated  in  a  protoplasmic  ground-mass.  It 
imparts  color  to  all  the  green  parts  of  the  plant.  Its  pres- 
ence is  absolutely  necessary  in  all  plants  that  secure  their 
nourishment  wholly  or  in  part  from  the  air  and  from  mineral 
matter  of  soil.  Review  Chapter  XIV.  Most  parasites  and 
saprophytes  do  not  bear  chlorophyll,  but  live  on  organic 
matter  (Chapter  XV).  The  oval  bodies  in  the  cell  of  Figs. 
468,  470,  471,  are  chloroplasts. 

451.  The  Cell  Contents. — The  products  formed  in  plants 
are  of  varied  character  and  exceedingly  large  in  number. 
Of  the  more  common  and  most  abundant  products  are  the 
following: 

Grape  (glucose  or  dextrose,  with  the  chem- 
ical formula  C6Hi206). 
Sugars  \   Fruit  (fructose  or  levulose  CeH^Oe). 

Cane  (saccharose  C12H22O11). 
Malt  (Maltose  C^H^Ou). 
(270) 


CHEMICAL    CONTENTS 


271 


Amyloses 
CeHioOs 


starch,  found  in  most  plants. 
dextrin  in  various  seeds. 
cellulose  in  date  seed. 
I  inulin  in  dahlia  tubers. 
Fats  and  oils,  as  in  flax  seed,  castor  bean,  cotton  seed, 

corn  and  other  seeds. 
Muscus  and  mucilage,  as  in  orchid  roots,  onions,  quince 

seed,  and  other  plants. 
Tannins,  as  in  oak  and  hemlock  bark,  persimmon,  and, 
in  general,  in  all  plants  that  are  astringent  to  the  taste. 
Glucosides.    Complex  products  which  on  digestion  yield 
glucose  sugar  as  one  of  the  products.    Amygdalin  of 
almond  and  peach  nut,  and  indican  of  the  indigo  plant, 
which  yields  the  indigo  dye,  are  examples. 
452.  Some  of  the  cell  contents  are  alkaloids,  complex  nitro- 
genous products,  of  which  the  following  may  be  mentioned: 
atropin,  in  belladonna. 
nicotin,  in  tobacco. 
emetin,  in  ipecac  root. 
caffein,  in  coffee. 
strychnin,  in  nux  vomica. 
morphin,  in  Papaver  somniferum  (opium 

poppy). 
quinin,  in  cinchona   or   Peruvian   bark 
tree. 
Resins,  as  in  Coniferae. 
Gum-resins,  Caoutchouc,  as  in  India-rubber  plant. 

formic,  as  in  stinging  nettles. 
acetic,  as  in  fermented  cider. 
oxalic,  mostly  in  form  of  calcium 

oxalate. 
malic,  as  in  apple. 
citric,  as  in  lemon. 
And  many  others. 


Alkaloids 


Vegetable  acids 


272      CONTENTS  AND  PRODUCTS  OF  CELLS 

453.  Other  cell  contents  are  the  proteids.  There  is  a  large 
number  of  different  proteids.  They  are  very  complex  organic 
products  composed  of  carbon,  oxygen,  hydrogen,  nitrogen, 
and  in  addition  sometimes  phosphorus  and  sulfur.  The 
white  of  egg  is  a  proteid.   The  protoplasm  itself  is  a  proteid. 

454.  Of  the  various  sugars  in  the  cell,  glucose  or  grape- 
sugar,  so  named  because  it  is  so  abundant  in  grapes,  is 
perhaps  the  most  common  in  plants  (179).  It  is  probably 
the  first  carbohydrate  formed  in  the  plant,  and  the  one 
from  which  all  others  are  derived.  It  is  also  a  product  of 
the  digestion  of  maltose,  which  in  turn  is  derived  from  the 
conversion  of  starch  in  the  plant.  It  is  also  one  of  the  sugars 
formed  from  the  digestion  of  cane  sugar.  It  is  very  soluble 
and  therefore  is  in  a  convenient  form  for  transportation 
from  one  part  of  the  plant  to  another.  Corn  syrup  is  glucose 
derived  from  starch  of  the  corn  kernel. 

455.  To  test  for  glucose:  Make  a  thick  section  of  a  bit  of 
the  edible  part  of  a  pear  and  place  it  in  a  bath  of  Fehling's 
solution.  After  a  few  moments,  boil  the  liquid  containing 
the  section  for  one  or  two  minutes.  It  will  turn  to  an  orange 
color,  showing  a  deposit  of  an  oxid  of  copper  and  perhaps 
a  little  copper  in  the  metallic  form.  A  thin  section  treated 
in  like  manner  may  be  examined  under  the  microscope, 
and  the  fine  particles,  precipitated  from  the  solution  by  the 
sugar  of  the  pear,  may  be  clearly  seen.  Fructose  and  maltose, 
as  well  as  other  organic  substances,  give  a  similar  reaction 
with  Fehling's  solution.  In  the  case  of  fruits  and  other  com- 
mon products,  it  may  be  assumed  that  precipitation  of  the 
oxid  of  copper  is  due  to  glucose  or  fructose.  With  barley 
malt,  the  precipitation  of  the  copper  oxid  is  due  to  maltose. 
Test  various  fruits  by  boiling  them  in  water  in  a  test-tube, 
and  then  determine  whether  sugar  is  present  by  adding 
Fehling's  solution  to  the  extract  and  again  heating. — Feh- 
ling's solution  is  made  by  taking  one  part  each  of  these  three 
solutions  and  two  parts  of  water:  (1)   Copper  sulfate,  9 


*»*8BBi,. 


SUGARS,    OILS    AND    RESINS  273 

grams  in  250  c.c.  water;  (2)  sodium  hydroxid,  30  grams  in 
250  c.c.  water;  (3)  Rochelle  salts  (sodium  potassium  tartrate), 
43  grams  in  250  c.c. 

456.  Cane-sugar  is  stored  as  a  reserve  food  in  many 
plants.  In  the  maple  tree,  sugar-beet,  sorghum,  and  sugar- 
cane, cane-sugar  is  abundant.  Test  the  sugar-beet  for  glu- 
cose with  Fehling's  solution.  None  is  found.  Boil  a  piece 
of  sugar-beet  in  a  little  water  in  a  test-tube.  To  the  water 
first  add  a  drop  of  hydrochloric  acid.  When  cool  add  a 
pinch  of  sodium  carbonate  and  Fehling's  solution,  and  again 
heat.  A  precipitate  of  oxid  of  copper  is  obtained.  Cane- 
sugar  heated  in  the  presence  of  hydrochloric  acid  is  con- 
verted into  glucose  and  fructose.  This  is  one  test  for  cane- 
sugar.  Another  test  is  as  follows:  (1)  Make  a  thin  section 
of  sugar-beet  and  let  it  stand  a  few  minutes  in  a  strong 
solution  of  copper  sulfate.  Then  carefully  rinse  off  all  the 
salt.  (2)  Heat  in  a  very  strong  solution  of  potassium  hy- 
droxid. There  will  be  seen  a  blue  coloration  in  the  section, 
gradually  washing  out  into  the  liquid. 

457.  To  test  for  the  oil  content  of  the  cell:  Mount  a  thin 
section  of  the  endosperm  of  castor-bean  seed  in  water  and 
examine  with  high  power.  Small  drops  of  oil  will  be  abun- 
dant. Treat  the  mount  with  alcanin  (henna  root  in  alcohol). 
Half  an  hour  or  more  may  be  required.  The  drops  of  oil 
will  stain  red.   This  is  a  standard  test  for  fats  and  oils. 

458.  To  examine  gum-resin:  Mount  a  little  of  the  milky 
juice  of  the  leaf-stem  of  the  garden  poinsettia  (Euphorbia 
pulcherrima).  It  is  of  a  creamy  consistency.  Examination 
under  the  microscope  shows  that  it  is  not  white,  as  it  seems 
to  the  naked  eye.  The  particles  are  yellowish  or  colorless 
and  insoluble.  These  particles  are  gum-resin.  They  have 
been  emulsified  by  the  plant,  making  the  juice  appear  white. 

459.  Starch  is  the  most  abundant  of  the  solid  products 
of  the  cell.  Starch  grains  have  a  definite  form  for  each  group 
of  plants;  and  these  groups  can  be  determined  by  the  form 


274     CONTENTS  AND  PRODUCTS  OF  CELLS 

of  their  starch  grains.  Detection  of  adulteration  of  various 
products  containing  starch  is  accomplished  by  the  aid  of 
the  microscope.  This  method  is  now  particularly  important 
in  determining  adulteration  of  stock  foods.  In  potato  starch 
the  grains  are  ovate,  with  a  "nucleus"  near  one  end,  as 
shown  in  Fig.  444.  In  poinsettia  they  are  dumb-bell  shaped, 
with  two  nuclei.  (Fig.  444.)  In  corn  they  have  equal  diame- 
ters, with  radial  fissures.  In  Egyptian  lotus  they  are  forked 
or  branched.  So  far  as  known,  all  starch  grains  are  marked 
with  rings,  giving  a  striated  appearance,  due  to  the  differ- 
ence in  density  of  the  layers.-  When  all 
water  is  driven  out  of  the  starch,  the  rings 
disappear.  The  layers  are  more  or  less 
concentric,  and  are  formed  about  a  starch 
nucleus. 

460.  Starch  grains  may  be  simple,  as 
found  in  potato,  wheat,  arrow-root,  corn, 

444.  Starch  grains.  . 

a,  potato;  b,  poinsettia;      and  many  others;  or  they  may  be    m 
c' nce"  groups    called    compound    grains,   as    in 

oats,  rice  (Fig.  444),  and  many  of  the  grasses. 

461.  Starch  may  be  found  in  all  parts  of  the  plant.  It 
is  first  formed  in  presence  of  chlorophyll  in  daytime,  mostly 
in  the  leaves,  and  at  night  it  is  converted  into  sugar  and 
then  it  is  carried  to  some  other  part  of  the  plant,  as  to 
the  roots  or  tubers,  to  be  stored  or  to  be  used.  When 
found  in  the  presence  of  chlorophyll,  it  is  called  transitory 
starch,  because  it  is  soon  converted  into  sugar  to  be  trans- 
ported to  other  parts  of  the  plant.  When  deposited  for  future 
use,  as  in  twigs  and  tubers,  it  is  stored  starch. 

462.  The  composition  of  starch  is  represented  by 
C6H10O5.  The  grains  are  insoluble  in  cold  water,  but  by 
saliva  they  are  changed  to  sugars,  which  are  soluble.  Great 
heat  converts  them  into  dextrine,  which  is  soluble  in  water. 
Starch  turns  blue  with  iodin  (76).  The  color  may  be  de- 
stroyed by  heat,  but  will  return  as  the  temperature  lowers. 


STARCH     AND     PROTEIDS  275 

463.  To  test  for  starch:  Make  pastes  with  wheat  flour, 
potato  starch,  and  corn  starch.  Treat  a  little  of  each  with 
a  solution  of  rather  dilute  iodin.  Try  grains  from  crushed 
rice  with  the  same  solution.  Are  they  the  same  color?  Cut 
a  thin  section  from  a  potato,  treat  with  iodin  and  examine 
under  the  microscope.  To  study  starch  grains:  Mount  in 
cold  water  a  few  grains  of  starch  from  each  of  the  following: 
potato,  wheat,  arrow-root  (buy  at  drug  store),  rice,  oats, 
corn,  euphorbia.  Study  the  sizes,  forms,  layers,  fissures, 
and  location  of  nuclei,  and  make  a  drawing  of  a  few  grains 
of  each. 

464.  Amylo-dextrine  is  a  solid  product  of  the  cell  much 
resembling  starch  in  structure,  appearance,  and  use.  With 
the  iodin-test  the  grains  change  to  a  wine-red  color.  Seeds 
of  rice,  sorghum,  wild  rice,  and  other  plants  contain  amylo- 
dextrine.  Amylo-dextrine  is  a  half-way  stage  in  the  con- 
version of  starch  into  maltose  and  dextrine.  These  latter 
substances  do  not  react  with  iodin. 

465.  Proteid  or  nitrogenous  matter  is  stored  largely  in 
the  form  of  aleurone  grains,  and  is  most  abundant  in  seeds 
of  various  kinds.  It  is  present  also  in  solution  or  in  amorphous 
compounds.  The  grains  are  very  small,  colorless  or  yellow- 
ish in  most  plants,  rarely  red  or  green.  In  the  common 
cereals  they  occupy  the  outer  layer  of  cells  of  the  endosperm. 
(Fig.  445.)  In  many  other  cases  they  are  distributed  through- 
out the  seed.     The  grains  vary  in  size  and    :!SB=S^SES_ -. 

form  in  different  species,   but   are   rather    ig|  ^--al 

constant  within  each  group.    They  are  en-     ^^^p^^fe] 
tirely  soluble  in  water  unless  certain  hard         «/"£,  --,\ 
parts   or   bodies,  known  as  inclusions,  are 

present,  and  these  may  remain  undissolved.        \an  in  kernel'1'^ 
The  inclusions  may  be  (a)  crystaloids,  as       wheat' 
in  potato,  castor-oil  seed;  (b)  globoids,  as  in  peach,  mustard; 
(c)  calcium  oxalate  crystals,  as  in  grape  seed. 

466.  To  study  aleurone  grains  and  their  inclusions:  Cut 


276  CONTENTS    AND    PRODUCTS    OF    CELLS 

a  thin  cross-section  of  the  peripheral  cells  of  a  grain  of  wheat 
and  mount  in  alcohol.  Stain  with  an  alcoholic  solution  of 
iodin  to  color  the  grains  yellow,  and  examine  with  the  high- 
est power.  Make  a  sketch  of  a  few  layers  of  cells,  just  be- 
neath the  epidermis.  Make  a  sketch  of  a  few  of  the  grains 
removed  from  the  cells.  While  looking  at  the  mount,  run  a 
little  water  under  the  cover-glass  and  watch  the  result. 
Make  a  similar  mount  and  study  of  the  endo- 
sperm of  castor-oil  seed,  or  of  grape  seed.  In 
the  castor-oil  seed,  look  for  inclusions  of  large 
crystaloids  and  small  globoids.  In  the  grape 
seed,  globoids  should  be  found  with  crystals  of 
calcium  oxalate  within  tHem.  This  experi-  446  Raphideg  of 
ment  will  require  the  power  of  one-sixth  or  rhizome  of  skunk 
one-fifth  inch  objective. 

467.  Cells  may  contain  crystals.  Besides  the  crystals 
found  as  inclusions  of  aleurone  grains,  many  others  occur. 
In  onion  skin  they  are  prisms;  in  nightshade  they  are  in 
the  form  of  crystal  flour;  in  the  petioles  of  the  peach  they 
are  roundish,  with  many  projecting  angles;  in  the  root-stock 
of  skunk  cabbage,  in  the  bulbs  of  hyacinth,  and  leaves  of 
tradescantia  they  are  needle-shaped  and  are  called  raphides. 
(Fig.  446.)  In  the  leaf  of  the  India-rubber  plant  (common 
in  greenhouses)    are   found  compound  clusters   resembling 

bunches  of  grapes,  which  are  called  cysto- 
liths.  (Fig.  447.)  These  are  concretions  and 
not  true  crystals.  In  saxifrage,  mineral 
matter  appears  as  incrustations  on  the  sur- 
face of  the  plant.  Toward  autumn,  crystals 
of  calcium  oxalate  become  very  abundant  in 
447.  Cystoiith  in  leaf  the  leaves  of  many  deciduous  trees;  examine 
of  rubber  plant.—    cr0ss-sections  of  peach  petiole  in  June  and 

Ficus  elastica.  c  r 

again  in  October. 

468.  To  study  crystals  and  cystoliths:  Section  the  root- 
stock    of    skunk    cabbage    or    Jack-in-the-pulpit,    the    leaf 


CRYSTALS  277 

of  Ficus  elastica,  the  leaf  of  ivy  (Hedera  helix);  make  a 
separate  mount  of  each  in  water,  and  examine  with  the 
high  power.  When  the  crystals  are  found,  draw  them,  with 
a  view  of  the  adjacent  cells.  Make  a  similar  study  of  a 
bit  of  thin  onion  skin. 

Review. — Name  ten  classes  of  contents  or  products  of  the  cell. 
Where  found?  Of  what  use?  What  is  chlorophyll?  What  is  its  use? 
What  is  assimilation  (185)?  Give  outline  of  the  products  of  cells 
found  dissolved  in  cell-sap.  What  are  the  uses  of  sugar  to  plants? 
Name  some  kinds  of  sugar  found  in  plants.  Describe  an  experiment 
to  test  for  glucose.  Same  for  cane-sugar.  How  may  we  find  the  oil 
in  plants?  Describe  an  experiment  for  the  study  of  gum-resin.  Why 
does  the  juice  containing  it  appear  white?  Describe  starch  grains  of 
potato.  Tell  how  starch  grains  of  other  plants  studied  differ  from 
those  of  potato.  What  are  the  uses  of  starch  to  the  plant?  Where 
is  the  plant's  starch  factory?  Describe  an  experiment  to  test  for  starch. 
Name  some  plants  in  which  one  may  find  amylo-dextrine.  How  does 
its  test  differ  from  that  for  starch?  What  are  aleurone  grains?  In 
what  cells  are  they  found  in  kernels  of  wheat?  Name  some  of  the  forms 
in  which  we  find  true  crystals  in  plant  cells. 

Note. — The  digestion  of  starch  is  produced  by  means  of  enzyms 
(183)  or  unorganized  ferments  (i.e.,  ferments  that  are  not  bacterial 
or  fungal,  but  are  chemical  substances).  These  ferments,  as  diastase, 
are  present  in  seeds  and  other  living  tissues  containing  starch.  During 
dormant  periods  the  enzyms  either  are  not  present,  or  their  action  is 
prohibited  by  the  presence  of  other  substances.  There  are  various 
specific  enzyms,  each  producing  definite  chemical  changes. 

Grape-sugar  and  its  associate,  fruit-sugar,  appear  to  be  the  forms 
most  generally  useful  to  plants.  Cane-sugar  is  readily  inverted  into 
these  sugars. 


CHAPTER  XXXVIII 

TISSUES 

469.  The  lowest  plants  are  unicellular  or  composed 
of  only  one  cell.  Of  such  are  bacteria.  (Fig.  136.)  All  the 
higher  plants  are  composed  of  collections  or  aggregations 
of  innumerable  cells:  they  are  multicellular.  If  we  ex- 
amine the  cells  of  the  stem,  the  leaves,  and  the  roots  of  any 
common  garden  plant  we  find  that  they  differ  very  widely 
from  each  other  in  shape,  size,  and  texture. 

470.  Any  group  of  similar  cells  is  called  a  tissue.  Each 
of  the  different  tissues  of  a  plant  has  its  own  type  of  cells, 
although  the  cells  in  a  tissue  may  differ  from  each  other 
in  various  minor  ways. 

471.  Parenchymatous  Tissue. — Thin-walled  cells  are 
known  as  parenchyma  cells.  When  they  unite  they  form 
parenchymatous  tissue.  These  may  or  may  not  be  elon- 
gated in  form,  and  they  usually  contain  protoplasm.  Paren- 
chymatous tissue  is  found  at  the  growing  point  of  a  shoot 
or  root  (Fig.  448);  in  the  mesophyll  (soft  pulpy  part)  of 
the  leaves  (Fig.  468) ;  around  the  vascular  bundles  of  stems 
and  roots  (Fig.  455/),  and  in  a  few  other  places,  as  pith, 
medullary  rays,  etc.  The  cells  of  this  tissue  may  be  meriste- 
matic — in  a  state  of  active  division  and  growth;  or  they  may 
be  permanent,  no  longer  able  to  divide. 

472.  One  important  use  of  this  tissue  is  to  form  other 
tissues,  as  in  growing  points.  Near  the  end  of  any  young 
root  or  shoot  the  cells  are  found  to  differ  from  each  other 
more  or  less,  according  to  the  distance  from  the  ponit. 
This  differentiation  takes  place  in  the  region  just  back  of 
the  growing  point.    In  the  mesophyll  (or  middle  soft  part)  of 

(278) 


THE     GROWING     POINT 


279 


leaves  the  elaboration  of  plant-food  takes  place.  Intercellular 
spaces  filled  with  air  and  other  gases  are  common  in  this 
tissue  of  leaves,  as  well  as  in  parenchyma  of  other  parts  of 
the  plant. 

473.  To  study  growing  points  use  the  hypocotyl  of  Indian 
corn.  Prepared  slides  may  be  secured  having  stained  longi- 
tudinal sections  of  the  hypocotyl.  The  median  section  should 
be  studied  with  the  high  power.  Note  these  points  (Fig. 
448) :  (a)  Root-cap  beyond  the  grow- 
ing point,  (b)  The  shape  of  the  end 
of  the  root  proper  and  the  shape  of 
the  cells  found  there,  (c)  The  group 
of  cells  in  the  middle  of  the  first 
layers  beenath  the  root-cap.  This 
group  is  the  growing  point,  (d)  Study 
the  slight  differences  in  the  tissues  a 
short  distance  back  of  the  growing 
point.  There  are  four  regions:  the 
plerome,  several  rows  of  cells  in  the 
center;  the  endodermis,  composed  of 
a  single  layer  on  each  side;  the  peri- 
blem,  of  several  layers  outside  the 
endodermis;  the  dermatogen,  on  the  448  Growing  point  of  root  of 

a        '  Indian    corn:   a,  cl,   dermatO- 

outer  edges.    Make  a  drawing  of  the      ^n-,  P,  Pl  peribiem;  e,  e,  en- 

,■  Tr  •  e   ii  dodermis;  pl,  p.croni";   i,  in- 

section.  It  a  series  ot  the  cross-sec-  itiai  group  of  ceils,  or  growing 
tions  of  the  hypocotyl  should  be  made  point  proper;  c'  root-cap- 
and  studied,  beginning  near  the  growing  point  and  running 
back  some  distance,  it  would  be  found  that  these  four  tissues 
become  more  distinctly  marked.  The  central  cylinder  of 
plerome  will  contain  the  ducts  and  vessels;  the  endodermis 
remains  as  endodermis;  peribiem  becomes  the  cortex  of 
parenchyma;  the  dermatogen  becomes  the  epidermis  of  the 
root. 

474.  Epidermal    Tissue     is    a    special    modification    of 
parenchyma,  comprising  the  thin  layers  on  the  exterior  ot 


280  TISSUES 

leaves  and  stems.  The  cells  are  often  tabular  or  plate-like  in 
form,  as  in  the  epidermis  of  leaves  (Fig.  137) ;  and  their 
outer  surface  bears  a  layer  of  cuticle,  a  protective  sub- 
stance which  is  insoluble  even  in  sulfuric  acid.  They  do  not 
bear  chloroplasts  and  often  contain  only  cell-sap,  with  a 
little  protoplasm.  Their  walls  are  much  thickened  in  some 
cases,  as  in  Figs.  447  and  471.  Hairs  and  bristles  are  con- 
sidered to  be  modified  epidermal  tissue. 

475.  Collenchymatous  Tissue. — Tissue  composed  of  cells 
thickened  at  the  angles,  not  much  elongated  and  not  lapping 
at  the  ends,  is  known  as  collenchyma.  (Fig. 
449.)  It  is  strengthening  tissue.  Good 
examples  are  found  in  such  vines  as 
pumpkin,  cucumber  and  gourd.  The  tis- 
sue is  slightly  elastic  and  allows  of  some 
stretching.  Cut  a  few  thin  cross-sections 
,,  of  large  stems  of  iewel-weed,  and  mount 

449.  Collenchyma  in  wild  °  0  ' 

jewel-weed  or   touch-  in  water.    Study  with  high  power. 

me-not  (impatiens).  ^     ^  g^  of  g.^  Tissue#_In  the 

higher  plants  is  a  tissue  known  as  soft  bast  or  sieve  tissue  (this 
also  forms  part  of  the  bundle;  476).  It  is  composed  of  two 
types  of  cells  which  almost  always  accompany  each  other. 
These  are  sieve  tubes  and  companion  cells.  (Fig.  450.)  Both 
are  elongated,  thin-walled  and  blunt  at  the  ends.  The  sieve 
tubes  are  so  called  because  of  the  sieve-like  areas  that  they 
bear  in  various  parts.  These  areas,  called  sieve  plates,  are 
commonly  at  the  ends  (as  partitions)  but  may  be  in  the 
lateral  walls.  (Fig.  450.)  They  serve  to  connect  the  cell- 
cavities  with  each  other,  and  through  them  the  proto- 
plasm strands  extend,  as  shown  in  the  figure. 

477.  Prosenchymatous  Tissue. — Several  elongated  and 
strong  tissues,  that  greatly  strengthen  the  stems  in  which  they 
are  found,  are  collectively  known  as  prosenchyma.  The  cells 
of  these  tissues  become  much  thickened  by  the  addition  of 
layers  to  the  inner  surface,  and  finally  lose  their  protoplasm. 


FROSENCHYMA 


281 


At  times  they  may  serve  as  store-rooms  for  starch  and 
other  products,  and  take  an  important  part  in  the  transfer 
of  the  plant  juices. 

478.  There  are  four  main  varieties  of  tissues  that  may  be 
included  under  prosen- 
chyma.  (1)  Fibrous  tissue, 
composed  of  very  thick- 
walled  cells  with  very 
small  central  cavities.  (F, 
Fig.  454.)  They  are  very 
long  and  tapering  at  the 
ends,  which  lap.  Such 
tissue  is  found  in  many 
plants  where  it  often 
wholly  or  in  part  surrounds 
the  fibro-vascular  bundles. 
It  is  more  often  but  not 
always  found  near  the  soft 
bast:  hence  the  cells  are 
sometimes  called  bast 
fibers  or  hard  bast.  (2) 
Wood  tissue,  or  wood  fibers. 
This  is  composed  of  cells 
much  like  the  preceding 
in  structure,  but  with 
thinner  walls  and  the  cen- 
tral cavity  not  so  nearly 
closed.  In  some  cases 
such  fibers  have  transverse  walls.  Wood  cells  constitute 
a  large  part  of  the  wood  of  some  plants  and  in  other 
cases  are  scattered  only  among  the  other  prosenehyina. 
(3)  Tracheids.  Cells  of  this  tissue  differ  from  ordinary 
cells  in  being  supplied  with  numerous  bordered  pits  or 
other  characteristic  markings.  They  constitute  almost  all 
of  the  wood  of  the  pines  and  other  gymnosperms.     (Fig. 


450.  Bast-tissue. 

panion  cell;  p,  shows  a  top  view  of  a  sieve 
plate,  with  a  companion  cell,  c,  at  the  side 
o,  shows  sieve  plates  in  the  side  of  the  eeh 
In  s,  s,  the  protoplasm  is  shrunken  from  the 
walls  by  reagents. 


282 


TISSUES 


451.)  (4)  Vascular  tissue,  composed  of  large  cells  which 
become  confluent  end  to  end,  forming  long  tubes  or  ducts. 
(TT',  Fig.  454.)  From  the  thickened  markings  which  these 
cells  bear  they  are  named  spiral,  annular,  pitted,  scalariform, 
etc.  (Fig.  441.)  These  vessels  are  often  of  considerable 
length,  but  are  never  continuous  through  the  entire  plant. 
Cut  a  grape-vine  stem  2  or  3  feet  long.  Place  one  cut  end 
in  a  glass  of  water  and  with  the  other  end  in  the  mouth, 

try  to  force  air 
through  the  stem. 
If  not  successful, 
shorten  the  stem 
a  little. 

479.  Scleren- 
chymatous  or 
Sclerotic  Tissue. 
— Sclerenchyma 
cells  are  hard,  not 
elongated,  often 
somewhat  spheri- 
cal, and  their 
thickened  walls 
are  provided  with 
simple  or  branch- 
ing canals.  The 
cells  of  this  tissue 
are  illustrated  by  the  common  grit  cells  of  the  pear  and  some 
other  fruits.  They  are  also  found  in  the  coats  of  many 
seeds,  in  nut  shells,  in  the  pith  of  some  plants.  Hold  a  large 
gritty  part  of  a  pear  between  two  pieces  of  smooth  elder 
pith  or  cork  and  make  free-hand  sections.  Mount  in  water. 
Make  a  drawing  of  a  single  cell  showing  thickness  of  wall, 
size  of  central  cavity,  wall  markings.  Note  the  general  shape 
of  the  cells. 

480.  Laticiferous  Tissue, — That  tissue  found  in  many 


451.  Longitudinal  tangential  section  of  Scotch  pine  wood, 
highly  magnified.  It  shows  tracheids  with  bordered 
pits.    The  dark  cells  are  cut  ends  of  medullary  rays. 


THE    TISSUE     SYSTEMS  283 

plants  which  contain  a  milky  liquid  is  called  laticiferous 
tissue.  There  is  no  fixed  type  for  the  vessels  that  carry 
this  fluid,  as  they  vary  greatly  in  different  plants,  being 
simple  in  the  asclepias  (milk-weed),  and  complex  in  the 
dandelion. 

481.  Tissue    Systems. — The    parts    of    complex    plants 
may  be   conveniently  grouped  into   three  tissue  systems: 

(1)  Fibro-vascular  tissue  system.  This  is  composed  of 
fibro-vascular  bundles.  The  fibrous  framework  of  roots, 
stems,  and  leaves  is  made  of  fibro-vascular  bundles.  ("Fibro- 
vascular"  means  fibrous  or  long  and  slender,  and  having  long 
openings  or  channels.)  Each  bundle  is  composed  of  two 
fundamental  parts:  phloem  and  xylem.  The  bast  fibers 
may  or  may  not  be  present.  Phloem  is  another  name  for 
the  soft  bast  or  sieve  tissue,  while  xylem  is  the  name  of  the 
lignified  or  woody  part,  and  is  composed  chiefly  of  the  wood 
cells,  tracheids,  and  ducts.  In  stems  of  dicotyledons  (exogens), 
these  two  parts  of  the  bundle  are  separated  by  cambium, 
a  meristematic  layer  giving  rise  to  xylem  on  one  side  and  to 
phloem  on  the  other.   For  types  of  bundles,  see  next  chapter. 

(2)  Fundamental  tissue  system.  This  is  composed  of  the 
parenchymatous  tissue  already  described.  The  fibrovas- 
cular  system  may  be  said  to  be  imbedded  in  the  funda- 
mental tissue.  (3)  Epidermal  tissue  system.  This  is  the 
covering  of  the  other  systems,  and  is  composed  of  epidermal 
tissue,  already  described.  It  should  be  borne  in  mind  that 
the  types  of  cells  and  tissues  as  defined  in  this  chapter 
are  not  all  that  may  be  found  in  plants.  There  are  many 
intermediate  forms,  e.g.,  tracheids  and  ducts  blend  the  one 
into  the  other ;  and  the  same  is  true  of  wood  cells  and  tracheids. 

482.  Summary  of  tissues  studied: 

1.  Parenchymatous  tissue. 

a.  meristematic. 

b.  permanent. 

2.  Epidermal  tissue. 


284  tissues 

3.  Collenchymatous  tissue. 

4.  Soft  bast  or  phloem  (sieve  tissue). 

5.  Prosenchymatous  tissue. 

a.  Fibrous  tissue  or  bast  fibers. 

b.  Wood  tissue  or  wood  fibers. 

c.  Tracheids. 

d.  Vascular  tissue  or  ducts. 

6.  Sclerenchymatous  or  sclerotic  tissue. 

7.  Laticiferous  tissue. 

8.  Tissue  systems. 

Review. — What  is  a  tissue?  How  may  two  tissues  differ?  What 
is  parenchymatous  tissue?  Name  three  places  where  this  is  found. 
Distinguish  between  meristematic  and  permanent  tissue.  Name  two 
uses  of  parenchymatous  tissue.  Of  what  utility  are  the  intercellular 
spaces  of  leaves?  Describe  the  parts  studied  in  the  section  of  root 
tip.  What  part,  of  this  tip  will  become  vascular?  Describe  epidermal 
tissue.  Collenchyma.  Sieve  tissue.  Of  what  use  are  the  sieve  areas? 
What  are  the  chief  uses  of  prosenchyma?  Describe  fibrous  tissue, 
wood  cells  or  wood  fibers;  tracheids;  ducts.  What  does  your  experi- 
ment in  blowing  air  through  a  grape-vine  stem  indicate?  Describe 
cells  of  sclerotic  tissue.  Laticiferous  tissue.  Name  three  tissue  systems. 
What  are  fibro-vascular  bundles?  What  two  classes  of  tissue  are  found 
in  each  bundle?   Of  what  is  phloem  composed?   Xylem? 


CHAPTER  XXXIX 

STRUCTURE   OF   STEMS  AND   ROOTS 


483.  There  are  two  main  types  of  stem  structure  in 
flowering  plants,  which  have  their  differences  based  upon 
the  arrangement  of  the  fibro-vascular  bundles.  These  types 
are  endogenous  and  exogenous. 

484.  Endogenous  Stems. — In  endogenous  stems,  the 
vascular  bundles  are  irregularly  scattered  through  the  funda- 
mental tissue  of  the  stem  (Fig.  452),  and  are  not  arranged 
in  circles  about  a  common  center.  These  plants  are  mono- 
cotyledons. The  bundles  are  not  -parallel  with  each 
other,  and  are  not  of  the  same  size  throughout  their  length. 
Fig.  453  shows  the  direction  often  taken  by  the  bundles 
in  the  stem.  On  the  exterior  there  is  either  an  epidermis 
or  a  false  rind.  The  only  trees  that  have  this  kind  of  stem 
are  natives  of  the  tropics  or  of  warm  countries.  The  palm 
is  one  of  them,  and  these 
stems  are  sometimes  called 
the  palm  type.  In  our 
climate  are  many  ex- 
amples, such  as  greenbrier, 
Indian  corn,  asparagus, 
grasses,  orchids,  iris,  and 
cat-tail. 

485.  To  study  arrange- 
ment of  bundles  in  corn: 
( Jut  thin  sections  of  a  small 
corn  stem  that  has  been 
preserved  in  alcohol.  Stain  with  hematoxylin';  or  the  sections 
may  be  examined  first  without  staining.    Examine  with  the 

(285) 


452.  Cross-section  of  oom-etalk,  showing 
the  scattered  fibro-vascular  bundles. 
Slightly  enlarged. 


286 


STRUCTURE  OF  STEMS  AND  ROOTS 


low  power,  and  make  a  sketch  showing  the 
arrangement  of  the  bundles.  The  sections,  if 
mounted  in  a  permanent  way,  as  in  balsam, 
may  be  kept  for  further  study  of  the  bundles. 
Compare  with  Fig.  454. 

486.  Exogenous  Stems. — The  fibro-vascular 
bundles  in  exogenous  (or  dicotyledonous)  stems 
are  arranged  in  a  circle  around  the  center, 
which  is  usually  filled  with  pith.  Outside  the 
ring  of  bundles  is  a  cortex  of  fundamental 
tissue.  Around  this  is  either  a  layer  of  cork 
or  an  epidermis.  Layers  of  parenchyma  cells, 
called  medullary  rays,  are  found  between  the  453.  Diagram 

bundles 


show  the  course 
of  fibro-vascular 
bundles  in  mono- 
cotyledons. 


454.  Fibro-vascular  bundles  of  Indian  corn, much 
magnified,  a,  annular  vessel;  a',  annular 
or  spiral  vessel;  tt',  thick-walled  vessels; 
w,  tracheids  or  woody  tissue;  f,  sheath  of 
fibrous  tissue  surrounding  the  bundle;  ft, 
fundamental  tissue  or  pith;  s,  sieve  tissue; 
p,  sieve  plate;  c,  companion  cell;  i,  inter- 
cellular space,  formed  by  tearing  down  of 
adjacent  cells;  w',  wood  parenchyma. 


and  often 
extending 
from  the  central  pith  to 
the  outer  cortex.  These 
usually  are  prominent  in 
young  stems  of  woody 
plants  and  in  vines.  (Fig. 
457.)  All  trees  and  nearly 
all  other  woody  plants 
of  the  temperate  regions, 
as  well  as  many  herba- 
ceous plants,  show  this 
plan  of  stem.  The  me- 
dullary rays  are  very 
prominent  in  oak  wood. 
These  rays  are  lignified 
in  the  xylem  part  of  the 
bundle  and  non-lignified 
in  the  phloem  part. 

487.  To  study  arrange- 
ment of  bundles  in  ex- 


EXOGENOUS    STRUCTURE 


287 


ogens:  Prepare  thin  cross-sections  of  the  stems  of  meni- 
spermum  (moonseed),  one  year  old,  of  geranium  or  of  tomato 
plant.  Other  greenhouse  or  garden 
plants  may  be  employed.  Stain  with 
hematoxylin.  Make  a  permanent 
mount.  Study  with  low  power,  and 
make  a  sketch  showing  the  shape  and 
location  of  the  fibro-vascular  bundles. 
(Fig.  455.)  Save  the  mount  for 
further  study.  If  menispermum  stems 
are  not  easily  obtained,  ivy  (Hedera 
helix),  clematis,  geranium,  coleus, 
tomato  or  other  plants  may  be  substi- 
tuted. In  woody  stems  the  compres- 
sion is  such  that  the  student  is  usu- 


455.  Arrangement  of  tissues  in 
2-yenr-old  stem  of  moonseed. 
/),  pith;  /,  fundamental  tis- 
sue; e,  epidermis.    The  fibro- 

vascuiar   bundles  are  very  ally  puzzled  to  understand  the  bundle 

The 


prominent. 


structure.  The  subject  will  be  sim- 
plified if  he  compares  (on  cross-section)  the  bundles  in  such 
a  plant  as  the  cucumber  with  that  part  of  the  vascular  ring 
that  lies  between  any  two  medullary  rays  in  one-year-old 
stems  of  peach, 
elm,  oak. 

488.  Other 
Stems. —  Be- 
sides the  two 
types  of  stems 
studied  above, 
which  are  prev- 
alent among 
phenogams, 
there  are  other 
kinds  of  struc- 
tures  of    stems 

among  the  Cryp-     456.  Cross-section  of  root  of  brake  (Pteris  aquilina),  showing 
tno-Qm  •      A  nnm  twelve   concentric  fibro-vascuhir  bundles.    The  two  long 

UU^dlllh.    A  tom-  dark  8tranc]8  are  composed  of  fibrous  tissue. 


288 


STRUCTURE  OF  STEMS  AND  ROOTS 


457.  Cross-section  of  fibro-vas- 
cular  bundle  of  moonseed  (see 
Fig.  455) .  /,  /,  crescent-shaped 
jheaths  of  bast  fiber;  p, 
phloem;  cp,  crushed  phloem; 
c,  cambium;  d,  xylem  ducts;  t, 
xylem  tracheids;  m,  medullary 
rays  of  fundamental  tissue; 
from  c  to  /  (at  bottom) ,  xylem ; 

1,  end  of  first  year's  growth; 

2,  end  of  second  year's  growth 
of  wood. 


mon  arrangement  of  the  bundles  is 
in  the  form  of  a  circle  some  distance 
from  the  center,  with  a  few  other 
bundles  within  the  circle.  Within 
the  circle  also  are  sometimes  large 
areas  of  fibrous  tissue.  (Fig.  456.) 
There  are,  however,  wide  variations 
from  this  structure,  but  this  mode 
of  arrangement  is  often  called  the 
fern  type  of  stem. 

489.  Three  Types  of  Bundles- 
It  has  already  been  said  (481)  that 
every  fibro-vascular  bundle  is  made 
up  of  two  parts:  (1)  phloem  or 
soft  bast;  (2)  xylem  or  wood.  The 
relative  position  of  these  two 
strands  of  tissue  is  very  important. 
There  are  three  plans  of  arrange- 
ment, on  which  three  types  of 
These  plans  are  collateral,  bi-collateral 


~*T5F3K 


bundles  are  based, 
and   concentric. 

490.  In  collateral  bundles,  the  phloem  and  xylem  are 
placed  side  by  side,  the 
xylem  being  nearer  the 
center  of  the  stem  and 
the  phloem  outside  or 
nearer  the  circumfer- 
ence of  the  stem.  This 
plan  occurs  in  the  stems 
of  phenogams.  The  col- 
lateral bundles  may  be 
either  open  or  closed. 
Open  bundles  are  those 
that    continue    to    in- 

.       .         ..„        45S.   Part  of  cross-section  of  root-stock  of  as 
Crease  in  Size  during  life         agus,  showing  a  few  fibro-vascular  bundle 


THE     STUDY     OF     BUNDLES  289 

by  the  presence  of  a  growing  layer  at  the  line  of  union  of  the 
phloem  and  xylem.  This  layer  of  growing  cells  is  called  cam- 
bium. Dicotyledonous  stems  have  open  collateral  bundles. 
( Fig.  455.)  Closed  bundles  are  those  that  cease  growing  very 
early  and  have  no  cambium  or  growing  layer.  They  are  called 
closed,  perhaps  from  the  fact  that  there  is  no  means  by  which 
they  may  become  larger.  Stems  of  monocotyledons  have 
bundles  of  the  closed  collateral  type.  Examine  with  high 
power  cross -sec- 
tions of  menisper- 
mum  stems  and 
corn  stems  (see 
Figs.  454, 455, 457), 
that  have  been 
stained  with  hema- 
toxylin. Study 
tissues  found 
single  bundle  of 
each,  with  the  aid 
of  the  illustrations. 
491.  In  concen- 
tric bundles,  the 
xylem    is  centrally 


in  a  in 


placed       in        the  459.  Enlargement  of  a  single  concentric 

bundle      and      the  bundle  from  Fig.  458. 

phloem  is  all  around  it,  as  in  club  mosses  and  ferns  (Fig. 
456) ;  or  the  phloem  is  in  the  center  of  the  bundle  and  the 
xylem  surrounds  it,  as  in  the  underground  stems  of  some 
monocotyledons,  as  asparagus.     (Figs.  458,  459.) 

492.  To  see  concentric  bundles:  Prepare  cross-sections 
of  the  stem  of  pteris  or  aspidium.  They  should  be  cut  very 
thin  and  stained  with  hematoxylin.  Make  a  sketch  showing 
the  arrangement  of  bundles.  Bicollateral  bundles  differ 
from  the  collateral  in  having  additional  phloem  on  the  inner 
side  of  the  xylem  strand;  as  in  pumpkins  and  squashes, 
s 


290 


STRUCTURE  OF  STEMS  AND  ROOTS 


493.  In  roots,  the  phloem  and  xylem  are  not  definitely 
arranged  in  bundles,  but  in  alternating  radial  strands  or 
plates.  This  plan  is  typical  in  young  roots  and  rootlets, 
but  is  more  or  less  obscured  in  older  ones  as  seen  in  Fig.  467. 


460.  Microphotograph  of  cross-section  of  grape  cane  of  a  single  season's  growth;  a 
cambium;  a-b,  phloem;  a-c,  xylem;  b-d,  periderm  layer,  derived  from  phellogen, 
which  cuts  off  the  cortex,  d-e,  with  its  primary  bast  bundles.  Note  large  medullary 
rays,  m,  and  the  large  ducts  for  water  conduction.  Compare  with  structure  of 
pine  wood,  Fig.  461. 


THE     ANNUAL    RINGS  291 

494.  Secondary  Thickening  of  Stems. — Dicotyledonous  (or 
exogenous)  stems  with  open  collateral  bundles  may  increase 
in  diameter  each  year.  If  they  are  perennial,  they  may  add 
a  ring  of  growth  each  spring.  (Fig.  461.)  These  rings  may  be 
counted  on  the  smooth  cross-cut  surface  of  a  tree,  and  the 
age  of  the  tree  usually  can  be  very  closely  determined.   All 


461.  White  pine  stem  five  years  old.    The  outermost  layer  is  hark. 

growth  in  thickness  due  to  the  formation  of  new  cells  out- 
side of  the  primary  wood  is  called  secondary  thickening. 

495.  As  we  have  seen  (490),  there  is  a  cambium  or  grow- 
ing layer  in  every  open  collateral  bundle  just  between  the 
xylem  and  phloem.  Each  spring  the  cells  of  this  layer  divide 
many  times  and  form  new  cells  both  inside  and  outside  the 
cambium  ring.  (Figs.  462,  463.)  Those  formed  inside 
become  thick-walled  and  are  xylem.  Those  formed  to  the 
outside  of  the  ring  are  gradually  changed  into  phloem.  The 
crowding  of  the  cells  within  the  cambium  ring  causes  the 


292 


STRUCTURE  OF  STEMS  AND  ROOTS 


ring  itself  to  enlarge  its  circumference  and  to  move  out- 
ward by  this  growth. 

496.  To  study  secondary  thickening:  Cut  thin  cross- 
sections  of  basswood  stems  of  different  ages  (one  to  three 
years  old).   Stain  and  mount.   Examine  with  low  power  and 


462.  Microphotograph  of  cross-section  showing  secondary  growth  in  larch,  June 
13;  a,  cambium;  a-b,  new  phloem;  a-c,  new  wood.  D.  Tagential  section  of  wood 
of  pine,  showing  transverse  section  of  medullary  rays;  rd,  transverse  resin-duct. 

sketch  the  arrangement  of  bundles  in  the  oldest  and  young- 
est. Note  the  effect  of  growth  on  the  medullary  rays.  Test 
them  with  iodin  for  starch.  Now  with  the  high  power 
study  the  peculiar  character  of  the  bast  tissue.  Note  the 
abundance  of  fibrous  tissue  all  through  it.  Draw  a 
single  bundle  from  the  stem  one  year  old,  carefully  show- 
ing the  location  of  the  cambium  and  the  different  tissues 
in  the  xylem  and  phloem  strands.  (Fig.  464).  It  may 
be  thought  best  to  precede  this  experiment  with  a  similar 
study    of    two-year-old   stem   of   moonseed,   ivy   or   other 


THE    BARK 


293 


403.  Cambium  tissue  a-b,  in  larch,  May  20.  Lower 
quarter,  cells  of  old  xylem.  Upper  quarter, 
cells  of  old  phloem.  Diameter  increase  just 
about  to  begin.  Medullary  rays  are  shown. 
Magnification  500  times. 


497.  Bark. — In  most 

woody  plants,  that  part 

of    the    stem  which    is 

outside    the    cambium 

ring  is  called  bark.    At 

first   it   contains   the 

epidermis  or  outer  layer 

of    cells,    the    phloem 

and    the    cortex    lying 

between   the    epidermis 

and   the  phloem.     The 

gradual  growth  of    the 

stem    causes  the   outer 

dead    layers   of    bark 

to    crack   more   or   less 

irregularly    and    finally 

to  split  off.    Examples  of  this  can  be  seen  on  the  trunks 

of  any  large  trees.     Before    the    tree   is  many   years  old, 

the  cortical   cells  of  the  bark  become  much  crushed  and 

are  lost  to  view.    The  epidermis  is  shed  rather   early  in 

the  life  of  the  tree. 

498.     Usually 

very  early   in   the 

life  of  the  stem  a 

corky  layer  of  bark 

is  produced.     This 

is  the  product  of  an 

active  layer  of  cells 

called  phellogen. 

This  layer  is  first 

found    at    those 

places  where  the 

'  **v.  stomates     were 

v  located.  The  epider- 

464.  Section  of  baaswood  stem,  five  years  old,  •     •     r-     +  -11 

The  cone-shaped  growths  of  phloem  are  plainly  seen.      mls  «  nrt>L  CTOW  U<  U 


294 


STRUCTURE  OF  STEMS  AND  ROOTS 


off  at  these  places,  and  the  rough  corky  spots  are  called 
lenticels.  Phellogen  is  very  active  in  the  cork  oak  of  Spain, 
but  it  occurs  in  nearly  all  woody 
plants.  In  such  plants  as  button- 
wood  (sycamore) ,  in  which  the  bark 
peels  off  in  thin,  flat  layers,  the 
phellogen  layer  is  nearly  uniformly 
active  in  all  parts,  while  in  many 
other  cases  there  is  very  little  uni- 
formity. In  wahoo  (burning-bush)  it  is  in  four  bands,  giv- 
ing rise  to  four  corner  wings.  In  the  section  of  menisper- 
mum  already  studied,  it  is  found  only  under  the  lenticel 
spots  where  the  stomates  have  been  located.  Fig.  465  shows 
structure  of  the  outer  bark  as  it  occurs  in  the  whole  circum- 
ference of  the  three-year-old  stem  of  red  currant. 

499.  To  study  phellogen  and  corky  tissue:  Cut  thin  cross- 


465.  Cross-section  of  red  cur- 
rant twig,  showing  bark. 
c,  corky  tissue;  p,  phellogen; 
g,  parenchyma  or  cortex 


466.  White  pine  stem  in  radial  longitudinal  section. 

Tracheids  on  the  left  with  medullary  rays  crossing  them.     Next  to  the  wood 

is  the  phloem,  then  fundamental  tissue,  then  the  dark  bark. 

sections  of  red  currant  from  stems  two  or  three  years  old 
that  have  been  kept  in  alcohol  at  least  several  hours.  The 
sections  should  be  stained.  With  the  highest  power  make 
a  careful  study  of  the  phellogen  and  the  corky  tissue  outside 


STRUCTURE    OF   ROOTS 


295 


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467.  Microphotograph  of  cross-section  of  root  of  grape  one  season  old;  m,  medullary 
rays;  a,  cambium;  o,  c,  phloem;  a,  6,  xylem. 

of  it.  Draw.  The  relation  of  bark  to  woody  tissue  in  pine 
is  shown  in  Fig.  461.  Cork  tissue  may  be  studied  to 
advantage  in  the  skin  of  the  potato. 

500.  Structure  of  Roots. — At  the  growing  point,  the 
root  has  a  cap  (of  small  compact  cells)  that  protects  the 
delicate  tissues  from  injury.    (Fig.  448.)    Such  a  protection 


296      STRUCTURE  OF  STEMS  AND  ROOTS 

does  not  occur  in  growing  points  (buds)  of  stems.  In  their 
internal  structure  roots  differ  from  stems,  especially  when 
very  young.  In  older  roots  the  differentiation  is  not  so 
marked.  (Fig.  467.)  Young  roots  have  the  radial  arrange- 
ment of  phloem  and  xylem  (490).  The  number  of  xylem 
strands  radiating  from  the  center  differs  with  the  plant. 
In  roots  also  there  is  almost  uniformly  a  true  endodermis. 
This  layer  is  just  within  the  cortex  and  is  composed  of 
rather  thick-walled  cells.  However,  many  rhizomes  and 
stems  have  a  true  endodermis. 

501.  To  study  pea  roots:  From  the  roots  of  the  pea 
a  few  weeks  old  cut  thin  cross-sections;  stain  and  mount. 
With  the  aid  of  the  low  power  make  a  sketch  showing  the 
arrangement  of  the  str&nds  of  wood  and  bast,  and  also  the 
amount  of  fundamental  tissue.  Use  the  highest  power  and 
draw  a  portion  including  one  strand  of  wood  and  two  of 
bast.  In  this  part,  draw  the  tissues  from  the  center  out 
beyond  the  endodermis.  Sections  may  also  be  made  of  the 
roots  of  germinating  pumpkins  or  squashes. 

Revjew. — Name  two  types  of  stems  occurring  in  flowering  plants. 
Describe  each  and  give  examples  to  illustrate  them.  Give  the  plan 
of  arrangement  of  bundles  in  fern  stems.  How  many  types  of  bundles 
are  there?  Upon  what  do  their  differences  depend?  Describe  and  give 
examples  of  collateral  bundles.  What  difference  is  there  between  open 
and  closed  collateral  bundles?  Give  examples  of  each.  Describe 
and  give  examples  of  concentric  bundles.  Radial  arrangement.  What 
is  secondary  thickening?  What  plants  show  it?  What  is  the  layer 
called  that  forms  the  new  cells  in  a  bundle?  When  is  this  layer  most 
active?  Describe  the  work  of  this  layer.  What  part  of  each  bundle  of 
a  dicotyledon  is  found  in  the  bark?  What  are  lenticels?  What  is  phel- 
logen?  Describe  the  work  of  phellogen  in  any  plant  you  have  studied. 
Whore  is  the  root  cap?  What  is  its  use?  Describe  fully  the  structure 
of  roots,  telling  how  they  differ  from  stems. 


CHAPTER  XL 

STRUCTURE   OF   LEAVES 

502.  Besides  the  framework  or  system  of  veins  found 
in  blades  of  all  leaves,  there  is  a  soft  tissue  (468)  called 
mesophyll  or  leaf-parenchyma,  and  an  epidermis  that  covers 
the  entire  outside  part. 

503.  Mesophyll. — The  mesophyll  is  not  all  alike  or  homo- 
geneous. The  upper  layer  of  it  is  composed  of  elongated 
cells  placed  perpendicular  to  the  surface  of  the  leaf.  These 
are  called  palisade  cells.  The  chlorophyll  grains  are  most 
abundant  in  them,  because  they  are  on  the  side  of  the  leaf 
most  directly  exposed  to  the  sunlight.  Below  the  palisade 
cells  is  the  spongy  parenchyma,  composed  of  cells  more  or 
less  spherical  in  shape,  irregularly  arranged,  and  provided 
with  many  intercellular  air  cavities.  (Fig.  468;  also  Fig. 
137.)  In  leaves  of  some  plants  exposed  to  strong  light 
there  may  be  more  than 
one  layer  of  palisade 
cells,  as  in  the  India- 
rubber  plant  and  ole- 
ander. Ivy,  when  grown 
in  bright  light,  will  de- 
velop two  such  layers  of       468.  Cross-section  of  ivy  leaf,  which  crow  in 

ii      i      j.  •        i       ill  shade  and   has  only  one    layer  of   palisade 

Cells,  but  in  Shaded  places  cells.    u,  upper  epidermis;   p,  palisade  cells; 

it    may    be     found     aS  in             C:  a  ^,stal;  sp'  sp°n^  Parenchyma;   i,  in- 

u  tercellular    space;    I,  lower  epidermis.    The 

Fig.  468.     Such  plants  as            Plan*  here  intended  is  the  true  or  English 

.    .               ,                                 ,  ivy,  Hedera  helix. 

ins  and  compass  plant, 

which  have  both  surfaces  of  the  leaf  equally  exposed  to  sun- 
light, usually  have  a  palisade  layer  beneath  each  epidermis. 

504.  Epidermis. — The  outer  or  epidermal  cells  of  leaves 

(297) 


u 


298 


STRUCTURE     OF    LEAVES 


do  not  bear  chlorophyll,  but  are  usually  so  transparent  that 
the  green  mesophyll  can  be  seen  through  them.  They  often 
become  very  thick-walled,  and  are  in  most  plants  devoid  of 
all  protoplasm  except  a  thin  layer  lining  the  walls,  the 
cavities  being  filled  with  cell-sap.  This  sap  is  sometimes 
colored,  as  in  the  under  surface  of  begonia  leaves.  It  is 
not  common  to  find  more  than  one  layer  of  epidermal  cells 
on  each  surface  of  a  leaf.  The  epidermis  serves  to  retain 
moisture  in  the  leaf.  In  desert  plants  the  epidermis  as  a 
rule  is  very  thick  and  has  a  dense  cuticle. 

505.  There  are  various  outgrowths  of  the  epidermis. 
Hairs  are  the  chief  of  these.  They  may  be  (1)  simple,  as 
on  primula,  geranium,  nsegelia;  (2)  once  branched,  as  on  wall- 
flower; (3)  compound,  as  on  verbascum  or  mullein;  (4) 
disk-like,  as  on  shepherdia  (Fig.  469);  (5)  stellate,  or  star- 
shaped,  as  in  certain 
crucifers.  In  some 
cases  the  hairs  are 
glandular,  as  in  Pri- 
mula sinensis  and  cer- 
tain hairs  of  pumpkin 
flowers. 

506.  To  study  epi- 
dermal hairs:  For  this 
study  use   the   leaves 
of    the    plants    men- 
tioned above  or  others 
that  may   be   substi- 
tuted.   Cross-sections 
may  be  so  made  as  to 
bring    hairs   on  the 
edge  of  the  sections.     Or,  in  some  cases,  the  hairs  may  be 
peeled  or  scraped  from  the  epidermis  and  placed  in  water 
on  a  slide.    Make  sketch  of  the  different  kinds  of  hairs. 
507.  Stomates  are  small  openings  or  pores  in  the  epi- 


469.  Disk-like  or  radial  hairs  of  shepherdi 


THE     STOMATES 


299 


dermis  of  leaves  and  soft  stems,  allowing  the  passage  of 

air  and  other  gases  and  vapors.    They  are  placed  near  the 

large  intercellular  spaces  of  the  mesophyll.  Fig.  470  shows 
the  usual  structure.  There  are  two  guard- 
cells  at  the  mouth  of  each  stomate,  which 
may  in  most  cases  open  or  close  the  passage. 
It  is  commonly  thought  that  the  opening 
and  closing  of  the  guard-cells  is  in  response 
ranium  leaf,  show-  to  different  moisture  conditions  of  the 
ingtheguard-ceiia.     atmosphere.     When    the   air   is   dry   it   is 

assumed  that  the  stomates  close 

and  thus  retard   water  loss  from 

the  plant,  and    vice    versa.    The 

stomates     have     generally    been 

thought  to  regulate  transpiration. 

This   is  not  true.     In  Fig.  471  is 

shown  a  case  in  which  there  are      47i.  stomate  of  ivy,  showing 

.  ,  ,      ,       „  .  compound  guard-cells. 

compound  guard-cells,  that  of  ivy. 

On  the  margins  of  certain  leaves,  as  of  fuchsia,  impatiens, 

and  cabbage,  are  modified  stomates  known  as  water-pores. 

508.  Stomates  are  very  numerous,  as  will  be  seen  from 
the  numbers  giving  the  pores  to  each  square  inch  of  leaf 

SUn  ace  I  Lower  Upper 

.surface  surface 

Peony 13,790  None 

Holly 63,600  None 

Lilac    160,000  None 

Mistletoe 200  200 

Tradescantia 2,000  2,000 

Garden  Flag 11,572  11,572 

The  arrangement  of  stomates  on  the  leaf  differs  with 
each  kind  of  plant.  Figs.  472  and  473  show  stomates  on  two 
plants,  and  also  the  outlines  of  contiguous  epidermal  cells. 
The  guard-cells  contain  chloroplasts. 

51 >'.».  Fall  of  the  Leaf. — In  most  common  deciduous  plants, 
when   the   season's  work  for  the  leaf  is  ended  some  of  the 


300  STRUCTURE     OF    LEAVES 

nutrients  are  withdrawn  into  the  stem,  and  a  layer  of  corky- 
cells  is  completed  over  the  surface  of  the  stem  where  the 
leaf  is  attached.  The  leaf  soon  falls.  It  often  falls  even 
before  killed  by  frost.  Deciduous  leaves  begin  to  show 
the  surface  line  of  articulation  in  the  early  growing  season. 
This  articulation  may  be  observed  at  any  time  during  the 
summer.  The  area  of  the  twig  once  covered  by  the  petioles 
is  called  the  leaf-scar  after  the  leaf  has  fallen.  Figs.  57,  87, 
91  show  a  number  of  leaf-scars.  Fig.  474  shows  the  leaf- 
scar  in  the  form  of  a  ring  surrounding  the  bud,  for  in  the 
plane-tree  the  bud  is  covered  by  the  hollowed  end  of  the 
petiole;  sumac  is  a  similar  case.  Examine  with  a  hand- 
lens  leaf-scars  of  several  woody  plants.  Note  the  number  of 
bundle-scars  in  each  leaf-scar.  Sections  may  be  cut  through 
a  leaf-scar  and  examined  with  the  microscope.  Note  the 
character  of  cells  that  cover 
the  leaf-scar  surface.  Com- 
pare 216. 


472.  Stomates  of  geranium  leaf.  473.  Grouped  stomates  on  a  begonia  leaf. 


Review. — Name  three  tissues  found  in  leaves.  On  the  board, 
draw  a  sketch  showing  the  structure  of  a  leaf  as  seen  in  cross-section. 
What  cells  of  leaves  bear  protoplasm  and  chlorophyll?  Why  do  some 
leaves  have  palisade  cells  near  both  surfaces?  Describe  epidermal 
cells.  Why  are  their  walls  much  more  thickened  in  some  plants  than 
in  others?  What  is  the  purpose  of  epidermis?  What  are  stomates?  Draw 
on  the  board  a  section  through  a  stomate  showing  epidermis  and 
mesophyll.  Give  some  idea  of  number  of  stomates  in  various  plants. 
Name  several  types  of  epidermal  hairs.  What  utility  could  be  suggested 
for  the  dense  coat  of  hairs  on  leaves  of  shepherdia?    (Fig.  469.) 

Note. — To  study  leaf  tissues:    A  number  of  leaves  can  be  com- 


HOW    TO    STUDY     LEAF    HISTOLOGY 


301 


pared  by  making  free-hand  cross-sections  of  leaves  held  between  two 
pieces  of  pith  or  cork,  and  mounting  the  material  in  water.  Study 
such  leaves  as  ivy  (Hedera  helix),  begonia,  cycas,  geranium,  and  corn. 
Note  the  number  of  layers  of  palisade  cells,  the  spongy  parenchyma, 
the  epidermal  layers.  Which  cells  bear  chlorophyll?  Write  a  brief 
description  of  the  tissues  of  each  leaf,  and  make  a  drawing  of  the  geranium . 

To  study  stomates  in  cross-section:  In  the  cross-sections  of  leaves 
of  geranium,  corn,  ivy,  lily,  or  spider-lily  prepared  for  the  above  exper- 
iment, look  for  the  stomates  and  make  a  careful  drawing  from  the  one 
you  can  see  best. 

Studrj  of  stomates  in  surface 
mew:  From  the  under  surface  of 
leaves  of  geranium  and  impatiens, 
peel  bits  of  epidermis  by  tearing 
the  leaf.  Mount  these  in  water 
and  examine  under  low  power. 
Are  the  stomates  scattered  or  in 


474.  Leaf-scar  of  the  plane-tree  or 
sycamore.  The  scar  surrounds 
the  bud,  which  was  covered  by 
the  hollow  base  of  the  petiole. 


groups?  With  the  aid  of  a  higher 
power,  draw  a  few  stomates  show- 
ing their  guard-cells  and  the  sur- 
rounding epidermal  cells.  Make 
a  similar  study  and  sketch  of  the  epidermis  torn  from  the  under  surface 
of  a  Begonia  sanguinea  leaf. 

The  openings  or  pores  are  known  as  stomata,  singular  stoma;  also  as 
stomates,  singular  stomate. 


Note  on  Scope,  Apparatus,  and  Methods. — The  work  outlined 
in  Part  III  is  sufficient,  if  well  done,  to  occupy  one  period  of  the  pupil's 
time  each  school  day  for  six  weeks.  These  chapters  are  intended 
only  as  laboratory  guides.  The  pupil  should  work  out  each  structure 
or  part  for  himself  before  taking  up  the  succeeding  subject.  The  work 
in  this  Part  deals  with  only  the  elements  of  the  subject,  but  it  is  as 
much  as  the  pupil  can  hope  to  take  up  with  profit  in  an  outline  course. 
Apparatus. — The  apparatus  necessary  for  the  work  outlined  in 
these  chapters  on  histology  may  be  secured  from  dealers  in  micro- 
scopes and  laboratory  supplies  at  a  low  figure.  Schools  should  obtain 
catalogues  from  the  following  and  other  reliable  dealers: 

Bausch  &  Lomb  Optical  Co.,  Rochester,  N.  Y. 

Eimcr  &  Amend,  New  York. 

The  Franklin  Educational  Co.,  Boston. 

Ward's  Natural  Science  Establishment,  Rochester. 

Richards  &  Co.,  Chicago  and  New  York. 


302 


STRUCTURE     OF    LEAVES 


Spencer  Lens  Co.,  Buffalo. 

Williams,  Brown  &  Earle,  Philadelphia. 

Geneva  Optical  Co.,  Chicago. 

Whitall,  Tatum  &  Co.,  New  York. 

Chas.  Lentz  &  Sons,  Philadelphia. 

Kny-Scheerer  Co.,  New  York. 

Cambridge  Botanical  Supply  Co.,  Cambridge,  Mass. 


475.   All  material  and  apparatus  should  be  kept  under  cover  when  not  in  use. 


The  microscope  should  have  a  1-inch  and  perhaps  a  2-inch  eye- 
piece, and  two  objectives  of  say  %  and  K  focal  lengths.  By  arrang- 
ing the  laboratory  study  of  the  pupils  at  different  times,  each  microscope 
may  be  used  by  three,  four,  or  even  more  pupils. 

There  should  be  a  microtome  or  section-cutter  for  use  by  the  class. 
If  possible,  each  pupil  should  have  his  own  individual  tools  and 
bottles  of  reagents,  as  follows: 

1  good  razor  (hollow-ground  on  one  side  only). 
1  small  scalpel. 

1  pair  forceps. 

2  sharp  needles  mounted  in  handles  (as  penholders).  (Fig.  215). 
1  medicine  dropper. 

1  small  camel's-hair  brush. 
A  number  of  slides  and  cover-glasses. 
Of  reagents,  stains,  and  other  chemicals,  there  should  be  the  following : 


Glycerine. 

95  per  cent  alcohol. 

Canada  balsam. 

Xylol. 

Copper  sulfate  solution. 

Iodin  dissolved  in  water. 


Iodin  dissolved  in  alcohol. 

Potassium  hydroxide  solution. 

Fehling's  solution. 

Alcanna  (henna  root  in  alcohol). 

Formalin. 


Preparing  and  keeping  laboratory  material. — In  preparing  material 
for  the  experiments  outlined  in  Part  III,  the  pupil  or  teacher  will  find 


APPARATUS     AND     SUPPLIES  303 

it  best  to  secure  much  of  the  material  during  the  growing  season  and 
preserve  it  until  the  time  for  use.  Material  collected  can  be  prepared 
by  placing  it  immediately  in  95  per  cent  alcohol  and  then  transferring 
it  after  twelve  hours  into  70  per  cent  alcohol,  in  which  it  may  be  stored 
for  future  use.  Material  may  also  be  prepared  in  a  2  or  2%  per  cent 
solution  of  formalin.    Formalin  burns  the  skin. 

Free-hand  cutting  and  moulding. — To  cut  sections,  the  material 
may  often  be  held  between  pieces  of  pith  or  smooth  cork  by  the  fingers. 
The  material  and  sections  should  be  kept  wet  with  alcohol  during  the 
time  of  cutting. 

The  sections  when  cut  should  be  wet  in  water,  then  stained  with 
Delafield's  hematoxylin  for  a  few  minutes;  drain  off  the  hematoxylin 
and  rinse  with  water;  then  use  95  per  cent  followed  by  absolute 
alcohol,  to  extract  all  the  water  from  the  sections;  then  pour  on  xylol 
for  a  few  minutes.  If  the  section  is  too  heavily  stained,  some  of  the 
stain  may  be  removed  by  repeated  rinsing  with  water.  Mount  the 
section  on  the  slide  in  a  drop  of  balsam  and  cover  with  the  thin  cover- 
glass.    Mounts  so  made  are  permanent.' 

Hematoxylin  does  not  mix  readily  with  alcohol,  and  balsam  does 
not  mix  with  water  nor  with  alcohol.  Sections  mounted  before  they 
are  freed  from  water  become  cloudy  and  worthless. 

All  materials  should  be  kept  covered  when  not  in  actual  use,  and 
always  in  order.  (Figs.  475,  476.)  A  good  work-table  may  be  made  on 
the  side  of  the  school-room.    (Fig.  477.) 

Microtome  sectioning. — The  sectioning  may  be  improved  by  the 
use  of  a  hand  microtome,  that  may  be  purchased  of  a  dealer  at 
small  cost.  A  more  complicated  microtome  may  be  employed,  but  in 
this  case  the  material  must  first  be  imbedded  in  a  matrix  like  collodion, 
paraffine  or  other  substance.  This  imbedding  is  a  complex  process; 
the  material  must  first  be  treated  with  various  reagents.  The  method 
will  not  be  considered  here.  The  reader  should  refer  to  Chamberlain's 
"Methods  in  Plant  Histology"  or  to  Stevens'  "Plant  Anatomy"  for 
the  methods  necessary  and  for  directions  for  staining. 


470.   Box  of  microscope  slides,  and  a  packet  of  collodion  drying  in  a  glass  vessel. 


PART  IV.— THE  KINDS  OF  PLANTS 


PART  IV 

THE   KINDS   OF  PLANTS 

Number  of  Plants. — Above  120,000  distinct  kinds  or 
species  of  seed-bearing  plants  are  known  and  described. 
Probably  little  more  than  one-half  of  the  total  number  now- 
existing  on  the  earth  is  known.  Even  in  the  older  countries 
and  regions,  seed-bearing  plants  heretofore  unknown  to 
science  are  discovered  now  and  then.  Outlying  regions 
are  relatively  little  known  botanically.  Large  parts  of 
Africa,  South  America,  Central  America,  China,  Central 
Asia,  and  the  tropical  islands  are  only  imperfectly  explored 
for  plants.  Cryptogamous  plants  are  very  numerous  in 
kinds,  and  many  kinds — as,  for  example,  various  bacteria 
— are  almost  infinite  in  numbers  of  individuals.  In  the 
lower  ranges  of  cryptogamous  plants,  as  in  fungi  and  bac- 
teria, new  kinds  are  being  described  even  in  countries  in 
which  they  have  been  carefully  studied. 

Species. — Each  kind  of  plant  is  called  a  species.  There 
is  no  absolute  mark  or  characteristic  of  a  species.  Between 
many  kinds  there  are  intermediate  forms,  and  some  kinds 
vary  immensely  under  different  conditions.  What  one 
botanist  considers  as  a  distinct  species  another  botanist 
may  regard  as  only  a  variety  or  form  of  another  species. 
No  two  botanists  agree  as  to  the  number  of  species  in  any 
region.  Species  are  not  things  in  themselves.  In  practice, 
any  kind  of  plant  that  is  distinct  enough  to  be  recognized 
by  a  description,  and  that  is  fairly  constant  over  a  con- 
siderable territory,  is  called  a  species.  We  make  species 
merely  to  enable  us  to  talk  and  to  write  about  plants:  we 
must  have  names  to  call  them  by.  The  different  kinds  of 
(307) 


308  THE    KINDS    OF    PLANTS 

plants  are  the  results  of  evolution.  Probably  none  of  them 
was  created  in  the  beginning  as  we  now  find  it. 

Names  of  Species. — For  more  than  one  hundred  and 
fifty  years  (since  Linnaeus  published  "Species  Plantarum"  in 
1753),  species  have  been  known  by  two  names,  the  generic 
and  the  specific.  The  generic  name  is  the  name  of  the 
genus  or  group  to  which  the  plant  belongs:  it  corresponds 
to  a  surname.  The  specific  name  belongs  only  to  the  par- 
ticular species  or  kind:  it  corresponds  to  a  given  or  Chris- 
tian name.  Both  names  are  necessary,  however,  to  desig- 
nate the  species.  Thus  Quercus  is  the  generic  name  of 
all  the  oaks.  Quercus  alba  is  one  of  the  oaks  (the  white 
oak),  Q.  virginiana  (the  live-oak)  another.  All  maples  be- 
long to  the  genus  Acer,  and  all  elders  to  Sambucus.  The 
same  specific  name  may  be  used  in  any  genus,  as  the  same 
Christian  name  may  be  used  in  any  family.  Thus,  there 
is  a  Quercus  nigra,  Cyperus  niger,  Acer  nigrum,  the  word 
"niger"  meaning  black. 

By  common  consent,  the  oldest  proper  name  of  any 
species  must  stand.  If  a  species  happens  to  have  been 
named  and  described  twice,  for  example,  the  first  name,  if 
in  the  proper  genus,  must  hold;  the  later  name  becomes  a 
synonym.  It  sometimes  happens  that  the  same  specific 
name  has  been  given  to  different  plants  of  the  same  genus. 
Of  course  this  name  can  be  allowed  to  stand  for  only  one 
species,  and  the  other  species  must  receive  another  name. 
In  order  to  avoid  confusion  of  this  and  other  kinds,  it  is 
customary  to  write  the  author's  name  with  the  species- 
name  that  he  makes.  Thus,  if  Gray  describes  a  new 
Anemone,  his  name  is  written  after  the  plant-name:  Ane- 
mone cylindrica,  Gray.  The  author's  name  thus  becomes 
an  index  to  the  history  of  the  species-name. 

Plant-names  are  thrown  into  the  forms  of  the  Latin 
language.  When  plants  first  were  studied  seriously,  knowl- 
edge was  preserved  in  Latin,  and  Latin  names  were  used 


PLANT   NAMES  309 

for  plants.  The  Latin  form  is  now  a  part  of  the  technical 
system  of  plant  and  animal  nomenclature,  and  is  accepted 
in  all  countries;  and  the  Latin  language  is  as  good  as  any- 
other.  In  the  Latin  language  all  plant-names  have  gender, 
and  the  termination  of  the  word  usually  differs  in  each  gender. 
The  species-name  must  agree  with  the  genus-name  in 
gender.  Acer  is  neuter:  so  are  A.  rubrum  and  A.  nigrum. 
Cyperus  is  masculine;  so  is  C.  niger.  Quercus  is  feminine, 
although  masculine  in  form,  but  trees  and  shrubs  are  feminine 
in  Latin:  so  we  write  Q.  nigra.  Masculine,  feminine,  and 
neuter  endings  are  seen  in  Rubus  sativus,  Pastinaca  sativa, 
Pisum  sativum.   "Sati-vus"  means  cultivated. 

The  name  of  a  species  not  only  identifies  the  species,  but 
classifies  it.  Thus,  if  a  plant  is  named  in  the  genus  Acer, 
it  belongs  to  the  maples;  if  it  is  named  in  Fragaria,  it  belongs 
to  the  strawberries;  if  it  is  named  in  Pyrus,  it  is  allied  to 
apples  and  pears ;  if  it  is  HeUanthus,  it  is  one  of  the  sunflowers. 

Use  of  Knowing  Plant-names. — The  name  is  an  intro- 
duction to  the  plant,  as  it  is  to  a  person.  It  is  an  index 
to  its  history  and  literature.  It  enables  us  to  think  and 
to  speak  about  the  plant  with  directness  and  precision.  It 
brings  us  nearer  to  the  plant  and  increases  our  interest  in  it. 

The  name  is  a  means,  not  an  end.  Merely  to  know  the 
name  is  of  little  use  or  satisfaction.  Knowing  the  name 
should  be  only  one  step  in  knowing  the  plant.  Of  late 
years,  the  determining  of  the  names  of  plants  has  been 
discouraged  as  a  school-exercise.  This  is  because  all  in- 
quiry stopped  when  the  name  was  secured.  A  name  was  a 
stone  wall  when  it  should  have  been  a  gate. 

How  to  Find  Out  the  Names  of  Plants. — There  can 
be  no  short-cut  to  the  names  of  plants,  for  names  cannot 
be  known  accurately  until  the  plant  is  known.  The  name 
and  the  plant  should  be  indissolubly  associated  in  the  mind. 
Study  first  the  plant.  If  one  does  not  know  the  plant,  there 
is  no  occasion  for  knowing  its  name. 


310  THE    KINDS    OF    PLANTS 

Learn  first  to  classify  plants:  names  will  follow.  Look 
for  resemblances,  and  group  the  plants  around  some  well- 
known  kind.  Look  for  sunflower-like,  lily-like,  rose-like, 
mint-like,  mustard-like,  pea-like,  carrot-like  plants.  These 
great  groups  are  families.  The  families  of  plants  are  bet- 
ter recognized  by  studying  a  few  representative  plants  than 
by  memorizing  technical  descriptions.  Go  to  the  botany 
and  use  the  keys  in  these  families,  in  order  to  run  the  plant 
down  to  its  genus  and  species.  If  the  family  is  not  recog- 
nized, use  the  key  to  find  the  family.  Use  the  keys  at  first: 
gradually  discard  them.  When  one  looks  for  relationships, 
the  vegetable  kingdom  comes  to  have  continuity  and  mean- 
ing. Merely  to  know  names  of  plants  here  and  there  is  of 
little  use. 

It  is  unwise  for  the  beginner  to  try  first  to  find  the  name 
of  any  plant.  Let  him  first  examine  familiar  plants  or  those 
which  seem  to  be  related  to  other  plants  that  he  knows. 
Let  him  get  in  mind  the  bold  characteristics  of  the  families 
which  are  most  dominant  in  his  locality.  After  a  time,  in 
case  of  each  new  plant,  he  should  be  able  to  give  a  shrewd 
guess  as  to  its  family;  then  he  may  go  to  the  book  to  verify 
the  guess. 

In  the  following  Flora,  about  fifty  well-marked  families 
are  chosen  for  study.  Some  of  them  are  not  the  most  char- 
acteristic of  American  vegetation,  but  they  are  such  as 
afford  easily  accessible  species,  either  in  the  wild  or  in  culti- 
vation, and  which  are  not  too  difficult  for  the  beginner. 
The  pupil  should  begin  with  plants  of  which  he  knows  the 
common  names  or  with  which  he  is  familiar.  Several  plants 
should  be  studied  in  each  family,  that  he  may  grasp  the 
characteristics  of  the  family  and  thereby  be  led  to 
compare  plant-groups  and  to  clarify  his  perception  and 
widen  his  horizon.  When  these  families,  or  the  larger 
part  of  them,  are  understood,  if  the  pupil  desires  further 
knowledge  of  species,  he  may  go  to  the  regular  manuals  in 


THE    HERBARIUM  311 

which  species  are  grouped  or  classified  according  to  their 
natural  affinities.  It  is  well  to  study  more  than  one  plant  in 
a  genus  whenever  possible,  for  then  close  comparisons  can 
be  made. 

Making  a  Collection. — The  making  of  a  collection  of 
plants  focuses  one's  attention,  defines  one's  ideas,  and  affords 
material  for  study  at  any  season.  The  collecting  and  pre- 
serving of  plants  should  be  encouraged.  Not  until  one 
searches  for  himself,  and  collects  with  his  own  hands,  can 
he  know  plants.  The  collection  should  not  be  an  end,  how- 
ever. It  should  be  only  a  means  of  knowing  plants  as  they 
live  and  grow.  Too  often  the  pupil  thinks  it  sufficient 
merely  to  have  made  a  collection,  but  the  collection  of  itself 
is  scarcely  worth  the  while. 

Plants  are  preserved  by  drying  them  under  pressure. 
The  collection,  when  properly  arranged  and  labeled,  is  an 
herbarium.  Each  species  should  be  represented  by  sufficient 
specimens  to  display  the  stems,  foliage,  flowers,  fruits.  If 
the  plant  is  an  herb,  its  roots  should  be  shown.  There  should 
be  several  or  many  specimens  of  each  species,  to  show  the 
different  forms  that  it  assumes.  It  is  less  important  to 
have  an  herbarium  of  many  species  than  to  have  one  showing 
the  life-phases  of  a  few  species.  First  make  specimens 
of  the  common  species:  later  one  may  include  the  rare  ones 
if  he  choose,  although  an  herbarium  that  selects  plants 
merely  because  they  are  rare  is  of  little  account  except  as 
a  collection  of  curiosities.  The  commonest  plants  are  usually 
the  least  represented  in  herbaria. 

Dry  the  plants  between  blotters  that  arc  12  inches 
wide  and  18  inches  long.  These  blotters  are  called  "driers." 
They  may  be  purchased  of  dealers  in  botanical  supplies, 
or  they  can  be  cut  from  felt  "carpet  paper."  It  is  well  to 
place  the  specimen  in  a  folded  sheet  of  newspaper,  and 
then  lay  the  newspaper  between  the  driers.  If  the  specimens 
are  large  or  succulent,  three  or  four  driers  should  be  laid 


312  THE    KINDS    OF    PLANTS 

between  them.  The  sheets  may  be  piled  one  above  another, 
until  the  pile  becomes  so  high  (10-16  inches)  that  it  tends  to 
tip  ever.  On  the  top  place  a  board  of  the  dimensions  of  the 
drier,  and  apply  twenty  to  thirty  pounds  of  stones  or  other 
weight.  Change  the  driers — but  not  the  newspapers — once 
a  day  at  first,  laying  the  moist  driers  in  the  sun  for  a  time. 
In  a  dry  warm  place,  most  plants  will  dry  in  a  week  or  ten 
days.  When  thoroughly  dried,  they  retain  no  soft,  sappy, 
fresh-green  areas,  and  they  usually  break  if  bent  sharply. 
They  will  be  perfectly  flat. 

The  use  of  corrugated  paste-board  has  proved  very  satis- 
factory in  drying  specimens.  The  board  should  be  of  the 
same  size  as  the  driers.  Place  one  of  the  corrugated  boards 
upon  a  table;  over  it  lay  a  drier;  then  the  sheet  containing 
the  specimen;  over  this  a  drier;  then  another  corrugated 
board,  a  drier,  a  sheet  containing  specimens,  and  so  on.  The 
corrugations  of  the  board  provide  air  passages  for  the  re- 
moval of  moisture  absorbed  from  the  specimens  by  the  driers; 
and,  unless  very  succulent  plants  are  being  pressed,  it  is  not 
necessary  to  change  driers  at  any  time  while  the  specimens 
are  drying.  The  pile  should  be  weighted  as  described  above. 

The  specimen  may  now  be  secured  to  strong  white 
paper,  known  as  "mounting  paper."  The  regulation  size 
of  the  sheets  is  113^xl6J^  inches.  It  is  the  quality  of 
heaviest  ledger  paper.  By  the  ream,  it  can  be  bought  for 
one  cent  or  less  a  sheet.  The  specimen  should  be  large 
enough  nearly  or  quite  to  cover  the  sheet,  unless  the  entire 
plant  is  smaller  than  this.  It  may  be  glued  down  tight,  as 
one  pastes  pictures  in  a  scrap-book,  or  it  may  be  held  in 
place  by  strips  of  gummed  paper.  The  former  is  the  better 
way,  because  the  plants  are  not  so  easily  broken.  Only 
one  species  should  go  on  a  sheet.  In  one  corner,  glue  the 
label.  This  label  should  give  the  place  and  date  of  collecting, 
name  of  collector,  and  any  information  as  to  height,  color, 
nature  of  soil,  and  the  like.    Sooner  or  later,  the  label  should 


MAKING   THE    HERBARIUM 


313 


contain  the  name  of  the  plant;  but  the  name  need  not  be 
determined  until  after  the  plant  is  mounted.    (Fig.  478.) 

The  sheets  of  one  genus  are  laid  together  in  a  folded 
sheet  of  strong  straw-colored  paper.    This  folded  sheet  is 


f3  ^wMW 


"--"•-^V/  /<  i\"<- 


i' 


12? 


~w 

*^%^§gg- 

-3wW  tnfl './~», SR  /.'-. 

?••  -*-- 

•178.  An  herbarium  sheet.    In  this  case,  the  specimens  are  held  in  place 
by  strips  of  glued  paper. 

the  "genus  cover."  Its  size  when  folded  is  11^x163^ 
inches.  On  the  lower  left-hand  corner  the  name  of  the 
genus  is  written.  If  one  has  many  sheets  in  one  genus 
— say  more  than  20 — it  may  be  necessary  to  have  more  than 


314  THE    KINDS    OF    PLANTS 

one  cover  for  them.  The  covers  are  laid  in  cupboards  flat- 
wise, one  on  the  other,  and  the  sheets  then  retain  their 
shape  and  are  always  ready  for  use. 

Explanation  of  the  Flora. — The  following  Flora  con- 
tains 625  species  of  plants  in  294  genera  and  51  families. 
These  species  are  selected  from  common  and  representative 
plants,  in  the  hope  that  50  to  100  of  them  may  be  secured 
by  any  pupil.  The  pupil  should  collect  his  own  specimens 
as  far  as  possible,  and  he  should  press  and  preserve  them 
after  he  has  studied  the  structure.  Familiarity  with  100 
plants  will  give  the  pupil  a  good  grasp  of  plant  forms,  pro- 
vided he  does  not  stop  with  merely  acquiring  the  names  and 
pressing  the  specimens.  He  should  know  how  the  plants 
look,  where  they  grow,  how  they  associate  with  other  plants, 
how  long  they  live,  and  the  like. 

Avoid  the  use  of  keys  as  much  as  possible:  learn  to 
see  the  plant  as  a  whole :  go  directly  to  the  family,  if  possible. 
But  it  may  be  necessary  to  use  keys  at  first.  In  this  book 
coordinate  parts  of  the  key  are  marked  by  the  same  letter: 
e.g.,  f,  ff,  fff,  are  three  coordinate  entries.  Coordinate 
entries  are  also  introduced  by  the  same  catch-word,  as 
"flowers,"  "leaves,"  "fruit."  Using  a  key  is  a  process  of 
elimination.  First  try  the  plant  in  a;  if  it  does  not  belong 
there,  go  to  aa.  Then  repeat  the  search  in  d,  dd,  etc.,  until 
the  family  is  found. 

Synonyms  are  placed  in  parentheses  immediately  fol- 
lowing the  accepted  name.  Thus  "Impatiens  biflora,  Walt. 
(7.  fulva,  Nutt.)"  means  that  the  accepted  name  is  Walter's 
I.  biflora,  but  that  the  plant  is  also  known  by  Nuttall's 
name,  /.  fulva. 

Proper  pronunciation  is  suggested  by  the  accent,  which 
indicates  both  the  emphatic  syllable  and  the  length  of  the 
vowel.  The  grave  accent  C)  indicates  a  long  vowel;  the 
acute  ('),  a  short  vowel.  Terminal  vowels  are  pronounced 
in  Latin  words.    The  word  officinale  is  pronounced  offici- 


THE    KEY  315 

niiy-ly;  aurea  with  au  as  in  Laura;  virginiiina  with  the  a  as  in 
hay;  alba,  with  a  as  in  had;  acutiloba  with  i  as  in  hill;  minor 
with  i  as  in  mine;  halimifolia  with  o  as  in  hole;  japonica  with 
o  as  in  con;  rumcx  with  u  as  in  tune;  funkia  with  u  as  in  run. 

Key  to  the  fumilics  as  represented  in  the  following  pages 

a.  CRYPTOGAMS:  no  true  flowers  or  seeds:  propagating  by  means 

of  spores Filices,  p.  321 

aa.  PHENOGAMS:  hearing  flowers  and  seeds. 

B.  Gymnosperms:  seeds  naked  (not  enclosed  in  ovaries),  borne 
in  cones  or  berries:  no  conspicuous  flowers:  lvs.  needle- 
shaped  or  scale-like:  plants  usually  evergreen Coniferae,  p.  324 

bb.  Angiosperms:  seeds  borne  in  ovaries:  flowers  usually  showy: 
leaves  very  various,  mostly  deciduous. 
C.  Monocotyledons:     cotyledon      1 :      leaves     mostly    parallel- 
veined,   not  falling  with   distinct   articulation:  stem  with 
scattered    fibro-vascular    bundles     (endogenous)    and    no 
separable  bark:  flowers  mostly  3-merous. 
d.   Flowers  without  true  perianth,   except  sometimes  small 
scales,    or    bracts,    or    bristles,    but    inclosed    by    green 
alternate  glumes,  or  chaffy  bracts:  arranged  in  spikes 
or  spikelets:  grass-like  plants. 
E.  Glumes  in  pairs,  of  2  sorts  (glumes  and  palets):  culms 
round,  hollow:  leaf-sheaths  usually  split  on  one  side 

opposite  blade 

Graminese,  or  Grass  Family,  not  treated  here. 

EE.   Glume   or   scale   single,    with   flower  in   axil:   perianth 

none  or  replaced  by  bristles:  culm  triangular,  solid; 

sheath  entire  or  closed 

Cyperaceee,  or  Sedge  Family,  not  treated  here. 
(For  grass-like  plants  having  flowers  with  G  similar,  green 
or  chaffy  bracts  [glumaceous  segments],  culms  solid, 
See  Juncaceae,  or  Rush  Family,  not  included  here.) 
DD.   Flowers  without   glumes,   borne  on  spadix,  small,   incon- 
spicuous, usually  attended  by  spathe Araceae,  p.  327 

ddd.  Flowers  not  on  spadices,  mostly  conspicuous. 
E.  Perianth  free  from  ovary. 

f.  The  perianth  with  all  parts  similarly  colored. 

g.  Parts    of    perianth    6,    similar,    green    or    chaffy 
(bract-like)  or  glume-like  (glumaceous  segments). 

Juncaceae. 
gg.  Parts  of  perianth  6,  regular,  colored  .  .  .  .Liliacex,  p.  328 
FF.  The  perianth  with  parts  differently  colored. 

g.  Leaves  in  a  whorl:  stigmas  3  .Trillium  in  Liliacese,  p.  332 
gg.  Leaves  alternate:  stigma  1 Commelinacese,  \>.  334 


316  THE    KINDS    OF    PLANTS 

ee.  Perianth-tube    adherent    to    ovary    wholly    or   partly: 
flowers  perfect. 

f.  Anthers  3 Iridaceae,  p.  337 

ff.  Anthers  6 Amaryllidaceae,  p.  335 

fff.  Anthers  1  or  2,  united  with  pistil,  gynandrous 

Orchidaceae,  p.  339 
cc.  Dicotyledons:  cotyledons  2  or  more:  leaves  mostly  netted- 
veined,   usually  falling  with  a  distinct  joint  or  articula- 
tion:  stem   with    concentric   layers   of   wood   when  more 
than  one  year  old   (exogenous),  and  a  distinct  separable 
bark:   flowers   mostly  5-merous  or  4-merous    (comprising 
the  remainder  of  this  key). 
d.  Choripetalse:    petals    distinct    or    wanting    (i.  e.,    flowers 
polypetalous,  apetalous  or  naked,  in  distinction  from 
gamopetalous,  dd,  p.  319). 
e.  Flowers  characteristically  apetalous;  mostly  small  and 
often  greenish,  inconspiciious. 
f.   Plants  woody. 

g.  The  flowers  monoecious  or  dioecious,  one  or  both 
sorts  in  catkins. 
H.  Fertile  flowers  in  short  catkins  or  heads:  calyx 
regular    in    the     pistillate     flower,     becoming 

fleshy  or  juicy  in  the  fruit  (juice  milky) 

Urticacese,  p.  345 
hh.   Fertile    flowers    1-3    in    a    cup-like    involucre: 
or  2  or  3  at  each  scale  of  the  pistillate  catkin: 
fruit   dry,    often   winged,    or   a    1-seeded    nut: 

sterile  fls.  in  elongated  catkins Cupuliferae,  p.  342 

gg.  The  flowers  not  in  catkins. 

h.  Calyx-tube  adherent  to  ovary :  climbing 

Aristolochiaceae,  p.  348 
hh.  Calyx-tube  hypogynous. 
i.  Leaves  opposite. 

j.  Fruit  a  double  samara,  2-winged 

Sapindaceae,  p.  343 
jj.  Fruit  a  single-winged    samara    or   1-seeded 

drupe:  stamens  2 Oleaceae,  p.  388 

jjj.  Fruit  not  winged:  3-seeded:  stamens  4 

Euphorbiaceae,  p.  351 
ii.  Leaves  alternate. 

j.  Styles  or  stigmas  2  or  2-cleft;  stamens 
equal    the    calyx-lobes    and    opposite    to 

them Urticacese,  p.  345 

jj.  Styles  or  stigmas  3,  each  2-cleft:  pod  3- 
■  celled  and  3-seeded:  flowers  3-parted: 
fruit  a  dry  capsule :  stamens  8  to  many. . . 

Euphorbiaceae,  p.  351 


THE    KEY  317 

ff.  Plants  herbaceous:  flowers  not  in  catkins  or  amenta. 
g.  Ovary  inferior,  6-celled:  stamens  6  or  12 

Arislolochiaccae,  p.  348 
gg.  Ovary  superior,  1-celled. 

h.  Stamens  indefinite Ranunculaceae,  p.  355 

hh.  Stamens  few  (4-12). 

i.  Styles  2-3:  stipules  sheathing  stem  at  nodes 

of  the  alternate  leaves Polygonacese,  p.  349 

ii.  Style  single:  stipules  not  sheathing  stem 

Urticaceae,  p.  345 

ggg.  Ovary  superior,  3-celled Euphorbiaceae,  p.  351 

ee.  Flowers  characteristically  polypetalous,  generally  showy. 
f.  Plants  woody. 

g.  The  stamens  numerous  (more  than  10). 
h.  Leaves  alternate. 

i.  Ovary  1,  simple  or  compound,  or  ovaries 
numerous;  fruit  a  drupe  or  fleshy:  stamens 
distinct,   inserted  on  the  cup-shaped  recep- 

tade Rosacea,  p.  385 

ii.  Ovaries  many  or  numerous:   stamens  many, 

monodelphous Malvaceae,  p.  372 

HH.  Leaves  opposite:  ovary  single,   2-5-celled:  fruit 

a  dry  capsule Saxifragacese,  p.  393 

gg.  The  stamens  10,  or  less  than  10. 

h.  Stamens  2  (rarely  or  accidentally  3  or  4):  fruit  a 

drupe,  or  2-celled  berry  or  2-celled  pod 

Olcaceae,  p.  420 
hh.  Stamens  5,  alternate  with  petals:  fruit  a  beny. 

Saxifragacese,  p.  393 
hhh.  Stamens  5  or  10  united  at  base,  some  sterile: 
leaves  simple:  fruit  5-lobed,  carpels  separating 

from    central   axis   when   ripe Geraniaceae,  p.  373 

hhhh.  Stamens  5-10:  leaves  compound:  fruit  a  leathery 
1-3-valved  pod  and  flower  irregular:  or,  fruit 
a  3-celled  inflated   (bladdery)  pod  and  flowers 

regular Sapindacese,  p.  375 

hhhhh.  Stamens    usually     10,    monadelphous,     diadel- 

phous,   or  distinct:    fruit  a   legume 

Leguminosae,  p.  379 
FF.  Plants  herbaceous. 

g.  The  stamens  10  or  more. 

h.  Ovary  1,  simple:  fruit  a  1-2-seeded  berry 

Berberidaceae,  p.  360 
hh.  Ovaries  several,  simple. 

i.  Stamens    indefinite,    hypogynous 

Ranunculaceae,  p.  355 


318  THE    KINDS    OF    PLANTS 

ii.  Stamens  indefinite,  inserted  on  cup-like  recep- 
tacle   Rosaceae,  p.  385 

hhh.   Ovary  compound. 

i.  Water    plants:    leaves    flat    and    floating,    or 

heart-shaped  and  erect Nymphaeaceae,  p.  361 

ii.   Land  plants. 

j.   Ovary  compound  and  1-celled. 

k.  With     central     placentae,     many-ovuled: 

plants  juicy  (watery) Portulacaceae,  p.  371 

kk.  With  2  or  more  parietal  placenta?:  colored 

or  milky  juice Papaveraceae,  p.  362 

kkk.   With  3  or  more  parietal  placentae:  leaves 
opposite:     juice     not     milky:      flowers 

yellow,  cymose Hypericaceae,  p.  370 

jj.   Ovary    compound,    several-celled:    stamens 

monadelphous Malvaceae,  p.  372 

GG.  The  stamens  10  or  less  in  number. 

h.   Ovary  single,  1-celled,  simple  or  compound. 
i.  Corolla  regular  or  nearly  so. 
j.   Sepals  and  petals  4-5  each. 
k.  Leaves    alternate. 

l.  Stigma  1 Leguminosae,  p.  379 

ll.  Stigmas  4 Saxifragaceae,  p.  393 

kk.  Leaves  opposite,  punctate:  flowers  yellow. 

Hypericaceae,  p.  370 
kkk.  Leaves  opposite,  not    punctate:    flowers 

pink,  red,  white Caryophyllaceae,  p.  353 

jj.   Sepals  2:  petals  4-5 Portulacaceae,  p.  371 

jjj.   Sepals    6:    stamens    hypogynous,    opposite 

to  the  petals Berbcridaceae,  p.  360 

ii.   Corolla  irregular. 

j.   Fruit  a  legume Leguminosae,  p.  379 

jj.  Fruit  a  capsule. 

K.  Petals  5:  stamens  5:  pod  1-celled,  3-valved. 

Violaceae,  p.  369 
kk.  Petals   4:   stamens   6,    diadelphous:   fruit 
2-valved    (globular)    1-seeded,    indehis- 

cent  in  Fumaria Fumariaceae,  p.  363 

hh.  Ovary  2-5-celled:  fruit  dry. 

i.   Fruit  of  2  dry  seed-like  carpels:  flowers  small, 

umbelled  or  in  heads:  stamens  5. .  Umbelh ferae,  p.  397 
II.  Fruit  a  2-celled  pod,  silique  or  silicle,  or  some- 
times loment,   or  indehiscent   and   nut-like: 
flowers  not  truly  umbelled,  but  solitary  or 
in  racemes. 

j.  Stamens  6:  sepals  4:  petals  (0  or)  4 

Cruciferae,  p.  365 


THE    KEY  319 

jj.  Stamens  4-8,  distinct  or  monadelphous;  fls. 
very  irregular:  sepals  5,  unequal  and  some 
of  them   colored:    petals  3    (or  5,   with   2 

scale-like):  pods  2-seeded Polygalaceae,  p.  378 

m.  Fruit  (or  ovary)  a  4-celled  capsule:  stamens  2, 

4  or  8:   petals  0,   2  or  4 Onagraceae,  p.  396 

mi.  Fruit  (or  ovary)  a  5-celled  capsule. 

j.  Leaves  simple,  evergreen:  seeds  minute, 
innumerable:  plants  white,  or  yellowish, 
parasitic  or  saprophytic  about  the  roots 

of  trees Ericaceae,  p.  423 

jj.  Leaves  simple,  more  or  less  lobed  or  divided, 
capsule  5-10-seeded:  or  stem  succulent 
and   translucent:   pod   walls   elastic,    each 

cell  several-seeded Geraniaceae,  p.  373 

jjj.  Leaves  compound,  palmately  3-foliolate.  .  .  . 

Oxalis  in  Geraniaceae,  p.  373 
mil.  Fruit  of  2  follicles,   seeds  hairy  tufted:  juice 

milky Asclepiadaceae,  p.  417 

DD.  Gamopetal^e:  corolla  in  one  piece,  at  least  toward  the 
base  (as  if  the  petals  were  more  or  less  united):  calyx 
and  corolla  both  present. 
E.  Stamens  more  numerous  than  corolla-lobes. 

F.   Ovary  1-celled,  1  parietal  placenta:  fruit  a  legume..  . 

Leguminosae ,  p.  379 
ff.   Ovary  3,  several-celled. 

g.  The   stamens    nearly  or    quite  free   from    corolla: 

style  1 Ericaceae,  p.  423 

gg.  The  stamens  free  from  corolla:  styles  5 

Oxalis  in  Geraniaceae,  p.  373 
GGG.  The   stamens   on    base   of   corolla-tube:    filaments 

monadelphous Malvaceae,  p.  372 

EE.   Stamens  as  many  in  number  as  the  lobes  of  the  corolla 
and  inserted  opposite  to  the  lobes:  ovary   1-celled: 

style  and  stigma  1:  pod  several  to  many-seeded 

Piiinulaceae,  p.  422 
kkk.   Stamens  equal  in  number  to  lobes  of  corolla  and  alter- 
nate with  them,  or  fewer  in  number. 
F.  Ovary  inferior. 

g.  The   stamens   distinct,   inserted  on   corolla,   4  or 
5:  ovary  2-5-celled. 

h.  Leaves  whorled  or  opposite  with  stipules 

Rubiaceae,  p.  426 

hh.  Leaves  opposite,  without  true  stipules 

Caprifolioceae,  i>.   127 
gg.  The   stamens   inserted   on   corolla   and   united    by 
anthers. 


^20  THE    KINDS    OF    PLANTS 

H.  Flowers  in  a  head  with  involucre  subtending. . . . 

Compositae,  p.  431 
hh.  Flowers  not  in  involucrate  heads,  but  separate: 

corolla  irregular Lobeliaceae,  p.  431 

ggg.  The    stamens    not    inserted    on    corolla    and    not 
united  to  each  other:  no  stipules:  juice  milky..  .  . 

Campanulaceae,  p.  430 
ff.  Ovary  superior. 

g.   Corolla    irregular:    stamens    4,    in    2    pairs:    or    2 
stamens:  the  ovary  deeply  4-lobed   around  the 
style:  fruits  4  dry  nutlets:  stem  square.. Labiatae,  p.  400 
gg.  Corolla  somewhat  irregular:  stamens  5,  inserted  on 
corolla. 

H.  The  ovary  deeply  4-lobed  about  the  style 

Echium  in  Borraginaceae,  p.  412 
hh.  The  ovary  not  lobed:  pod  many-seeded:   fila- 
ments all  or  some  woolly 

Verbascum  in  Scrophulariaceae,  p.  405 
ggg.   Corolla  regular:  stamens  equal  in  number  to  the 
lobes  of  the  corolla. 
h.  Ovaries  2,  distinct:    lvs.  opposite:  juice  milky: 
styles  or  stigmas  united  into  1. 
I.   Stamens  separate,  inserted  on  corolla:  corolla 
bell -shaped,      funnel-     or      salver  -  formed : 

pollen  granular,  as  usual Apocynaceae,  p.  418 

II.  Stamens  monadelphous,  anthers  attached  to 
stigma:  a  crown  of  hood-like  appendages  each 
containing  an  incurved  horn,  borne  on  the 
stamen-tube:  pollen  cohering  in  masses  (waxy 

or  granular) Asclepiadaceae,  p.  417 

hh.  Ovary  1,  deeply  4-lobed  around  style  (2-lobed 
in  Heliotropium). 
I.  Leaves  alternate:  plants  usually  rough-hairy.. . 

Borraginaceae,  p.  412 

ii.  Leaves  opposite:  stems  square 

Mentha  in  Labiatae,  p.  400 
Hhh.  Ovary    1,    not    deeply    lobed,    1-celled:    ovules 
parietal,  or  2  parietal  placenta?. 
I.  Leaves  simple,  entire,  opposite,  exstipulate. . .  . 

Gentianaceae,  p.  417 
H.  Leaves  toothed,  lobed  or  pinnately  compound, 

mostly  alternate Hydrophyllaceae,  p.  415 

Hiiiiii.   Ovary  not  deeply  lobed,  2-10-celled. 

i.  Leaves  none:  parasites,  twining 

Cuscuta  in  Convolvulaceas,  p.  411 
ii.  Leaves  opposite,  without  stipules. 


THE    KEY  321 

j.  Stamens  free  from  corolla  but  inserted  with 

it :  style  1 Ericaceae,  p.  423 

jj.  Stamens  inserted  on  tube  of  corolla. 

K.  Number  of  stamens  4  in  2  sets:  ovary 

2-4-celled  (cells  1 -seeded)...  Verbenacex,  p.  403 
ee.  Number  of  stamens  5  or  (rarely)  more. 

l.   Fruit  2  or  4   nutlets.  .  .  .Borraainacese,  p.  412 
ll.  Fruit  a  pod,  few-seeded. 

m.  Calyx  5-lobed:  styles  3-cleft 

Polemoniacese,  p.  416 
mm.  Calyx  5-lobed:  style  1  or  2,  or  2-cleft: 
ovary     2-celled     (rarely     3-celled): 
seeds  good-sized,    1   or  2  per  cell: 

generally  twining  herbs 

Convolvulacese,  p.  411 
lll.  Fruit  a  pod,  many-seeded,  or  a  berry: 

style  1 Snlanaceas,  p.  4(38 

gggo.  Corolla  regular  or  irregular:  stamens  fewer  than 
the  corolla-lobes. 
h.  Stamens     2:     ovary     4-lobed:     corolla     nearly 

equally   4-lobed Lycopus    in    Lobiatse,  p.  400 

hh.  Stamens  2  (rarely  3):  ovary  2-celled. 

i.  Woody  plants,  shrubs  or  trees:  corolla  regular, 

4-cleft Oleacese,  p.  420 

II.  Herbs:  corolla  wheel-shaped  or  salver-shaped, 
with   a   4-parted    (rarely   5-parted)    border, 

or  somewhat  irregular 

Veronica  in  Scrophulariaceae,  p.  408 


A.  CRYPTOGAMS. 

I.  FILICES.   Ferns. 

Herbaceous  and  leafy  plants,  ours  without  stems  or  trunks  above 
ground,  but  producing  perennial  rootstocks:  plants  flowerless  and 
seedless,  but  bearing  spores  in  sporangia,  the  latter  collected  into 
sori  which  are  usually  borne  on  the  under  side  or  margins  of  the  fronds 
and  which  are  sometimes  covered  with  an  indusium. — Most  abundant 
in  warm  countries,  of  about  4,000  species,  of  which  about  1G5  arc  na1  ive 
to  the  United  States.  The  leaflets  of  fern-fronds  are  pinna';  the  second- 
ary leaflets  are  pinnules. 

a.  Fruit  borne  in  contracted  panicles  or  on  specially  con- 
tracted  parts  of  the  frond,   these  parts  being  devoid 
of  resemblance  to  green  leaves. 


322 


THE    KINDS    OF    PLANTS 


B.  Sporangia  large  and  globose,  without  a  ring  of  special 

cells  running  around  their  margin 1.  Osmunda 

BB.  Sporangia  with  a  ring  of  prominent  elastic  cells  run- 
ning around  the  margin,  and  which  are  concerned 

in  the  dehiscence 2.  Onoclea 

AA.  Fruit  borne  on  the  back  of  green  fronds  (the  fruiting 
pinnse  sometimes  narrowed  but  still  leaf-like),  sporan- 
gia with  a  ring  of  elastic  cells. 

B.  Sori  naked  (no  indusium) 3.  Polypodium 

BB.  Sori  borne  under  the  reflexed  margins  of  the  frond. 
C.  Pinnse  entire  on  the  lower  edge,   somewhat  trian- 
gular in  outline 4.  Adiantum 

CC.  Pinnse  toothed  on  both  margins,  oblong  in  outline... 5.  Pteris 
BBB.  Sori  covered  with  a  distinct  scale-like  indusium. 

c.  Shape  of  sori  oblong. . . 6.  Asplenium 

cc.  Shape  circular. 

D.  Indusium  circular-peltate,  without  a  sinus 7.  Polystichum 

dd.   Indusium  reniform,  or  if  circular  with  a  narrow 

sinus 8.  Aspidium 

1.  OSMUNDA.    Flowering  Fern. 

Strong  ferns  from  stout  creeping  rootstocks,  with  large,  pinnate  fronds: 
sporangia  covered  with  interwoven  ridges,  but  wanting  the  elastic  ring  of 
most  ferns.    Inhabitants  of  bogs  and  wet  woods. 

O.  regalis,  Linn.    Royal  fern.    Top  of  the  frond  contracted  into  a  fruit- 
ing   panicle:    frond    2-pin- 
nate,  the  pinnae  oblong,  ob- 
tuse, and  nearly  entire. 
O.    Claytoniana,     Linn. 

-  ■<*$*?'*'      ^g-  4^9-    ^wo  to  *°ur  Pa^rs 

"^MffiJ0$w  ^ ^jffi&ftK    °f  Pmnse  near  tne  middle 

\""'!i^*';'  of  the  frond  contracted  into 

v?*&0*&fo,V*:^1*         fruit-bearing   parts:    pinnse 

linear-lanceolate  and  acute, 

deeply  lobed. 

0.   cinnamomea,    Linn. 
479.  Osmunda  Claytoniana  (left).     Osmunda         cinnamon   fern.     Fig.   479. 
cinnamomea.  '  . 

Some  fronds  entirely  con- 
tracted into  fruiting  parts,  and  these  cinnamon  colored  (whence  the  ver- 
nacular name):  sterile  form  with  the  fronds  much  like  those  of  0.  Clay- 
toniana in  shape  except  more  acute  at  top. 

2.  ONOCLEA.    Sensitive  Fern. 

Mostly  rather  strong  ferns,  with  broad  sterile  fronds  and  with  the  fertile 
fronds  rolled  into  hard  contracted  fruiting  bodies,  which  remain  after  the 
sterile  leafy  fronds  have  perished:  sporangia  with  an  elastic  marginal  ring 
of  cells.    Bogs  and  old  springy  fields. 


FERNS  323 

O.  sensibilis,  Linn.  Sensitive  fern.  Brake.  Fig.  337.  Sterile  frond 
triangular-ovate,  the  pinnae  not  extending  quite  to  the  midrib  and  toothed: 
fertile  frond  usually  lower  than  the  other  (1-2  ft.  high),  with  a  few  pinnae. 
Common  in  old  pastures. 

O.  Struthiopteris,  Hoffm.  Ostrich  fern.  Very  tall  (2-5  ft.),  the 
sterile  fronds  narrow,  once-pinnate,  with  long-lanceolate  acute-lobed 
pinna;:  fertile  fronds  much  shorter,  blackish,  with  many  pinnae. 

3.  POLYPODIUM.    Polypody. 

Small  ferns,  with  simple  or  once-pinnate  fronds  from  slender  creeping 
rootstocks:  sori  round,  borne  at  the  ends  of  little  veins.    On  dry  cliffs. 

P.  vulgare,  Linn.  Common  polypody  or  polypode.  Figs.  333,  334. 
Fronds  a  foot  or  less  tall,  narrow-oblong  in  outline,  pinnatifid,  the  lobes 
nearly  or  quite  entire:  fertile  pinnae  not  contracted. 

4.  ADIANTUM.    Maidenhair  Fern.    Fig.  336. 

Small  ferns  with  compound  forking  fronds  and  wedge-shaped  or  some- 
what triangular  pinnae,  shining  stipes  or  petioles,  and  sori  borne  at  the 
ends  of  the  veins  under  the  reflexed  margins  of  the  pinnae. 

A.  pedatum,  Linn.  Common  maidenhair.  Plant  2  ft.  or  less  high,  the 
leaves  forking  into  several  or  many  long  pinnae  which  bear  broad  pinnules 
notched  on  the  upper  margin.    Cool,  shadj-  woods.    Very  graceful. 

5.  PTfiRIS.    Brake. 

Coarse  ferns  of  mostly  dryish  places,  with  long  pinnae:  sporangia  borne 
beneath  the  reflexed  margin  of  the  pinnules,  on  small,  transverse  veins. 

P.  aquilina,  Linn.  Common  brake.  Figs.  139,  335.  Fronds  broadly 
triangular,  twice-  or  thrice-pinnate,  the  pinnules  long-lanceolate,  acuminate, 
and  lobed.  Common  in  sunny  places:  perhaps  our  commonest  fern.  Two 
to  3  ft.  high,  growing  in  patches,  particularly  in  burned  areas. 

6.  ASPLF,NIUM.    Spleenwort. 

Middle-sized  ferns,  mostly  with  pinnate  leaves:  sori  oblong  or  linear, 
borne  on  the  upper  side  of  a  veinlet,  or  back  to  back  on  opposite  sides  of 
the  veinlet,  these  veinlets  not  interwoven. 

A.  Filix-fcemina,  Linn.  Lady-fern.  Large,  the  fronds  2-3  ft.  tall, 
growing  many  together,  twice-pinnate,  the  pinnules  oblong-pointed  and 
sharp-toothed:  sori  short  and  close  together,  at  maturity  becoming  more 
or  less  continuous.    A  very  common  fern  in  moist  woods  and  copses. 

7.  POLfSTICHUM.   Christmas  Fern. 

Much  like  the  last  in  general  appearance,  but  the  sori  circular  and 
covered  with  peltate  indusia. 

P.  acrostichoides,  Kuntze  {Aspidinm  acrostichoides.  Swartz).  Christmas 
fern.  Figs.  331,  332.  Fronds  2  ft.  or  less  tall,  narrow,  once-pinnate,  the 
pinnae  serrate  and  bearing  a  larger  tooth  on  the  upper  side  near  the  base, 
the  terminal  part  of  the  frond  somewhat  contracted  in  fruit.  Common  in 
woods.    Nearly  or  quite  evergreen. 


324  THE    KINDS    OF    PLANTS 

8.  ASPIDIUM.    Shield  Fern. 

Resembles  Polystichum  but  with  reniform  indusia  or,  if  circular-peltate, 
having  a  distinct  sinus  along  one  side. 

A.  Thelypteris,  Swartz  (Dryopteris  The- 
lypteris,  Gray).  Marsh  shield  fern.  Fronds 
standing  2  ft.  high,  long-pointed,  once-pin- 
nate, the  pinnae  many-lobed,  the  margins  of 
the  fertile  fronds  revolute. 

A.   marginale,    Swartz    (Dryopteris  mar- 

ginalis,   Gray).    Fig.  480.    Large,   handsome 

,„„     .     ,  "     ""    ~ "T  ,  fern   growing    in    woods  and  ravines,   2  ft. 

480.   Aspidmm  marginale.  ,  •   ,       ,         ,  •  lL        . 

high:   fronds  once-pinnate,  the  pinna?  pinna- 

tifid  and  lance-acuminate:  sori  large  and  close  to  the  margin  of  the  frond: 

petiole  chaffy. 

AA.  PHENOGAMS:    B.  GYMNOSPERMS. 

II.  CONIFERiE.   Cone-bearing  or  Pine  Family. 

Woody  plants,  mostly  trees,  with  resinous  sap  and  stiff  needle- 
shaped  or  scale-like,  mostly  evergreen  leaves:  plants  bearing  no  ovaries, 
the  ovules  lying  naked  and  receiving  the  pollen  directly:  flowers 
diclinous  (usually  monoecious),  generally  in  scaly  catkins,  those  cat- 
kins bearing  the  pistillate  flowers  maturing  into  cones  but  sometimes 
becoming  berry-like  (as  in  junipers).  Above  300  species,  one-third 
of  which  inhabit  North  America:  particularly  abundant  in  elevated 
and  mountainous  regions. 

A.  Cone  dry,  with  overlapping  scales. 

b.  Scales  many  and  cones  1  in.  or  more  long. 

c.  Leaves  long  and  needle-like,  in  sheaths  or  bundles  of 

2-5,  persistent 1.  Pinus 

cc.  Leaves  short,  scattered,  persistent. 

d.   In  cross-section,  Ivs.  4-sided:  sessile 2.  Picea 

dd.  In  cross-section,  lvs.  flat:  short -petioled 3.  Tsuga 

ccc.  Leaves  short  but  very  slender,  in  clusters,  deciduous. 4.  Larix 

bb.  Scales  few  (3-12),  the  cones  about  Yi  in.  long 5.  Thuja 

aa.  Cone  modified  into  a  fleshy,  berry-like  body 6.  Juniperus 

1.  PINUS.    Pine. 

Trees  with  long,  persistent,  needle-shaped,  angled  leaves,  in  bundles  of 
2-5,  and  with  scale-like  deciduous  leaves  on  the  young  branchlets:  sterile 
catkins  usually  borne  at  the  base  of  the  new  shoot:  fertile  cones  maturing 
the  second  year,  often  hanging  on  the  tree  for  years:  cotyledons  several. 

P.  Strobus,  Linn.    White  pine.    Figs.  158,  299.    Large  forest  tree,  much 


PINES    AND    SPRUCES 


325 


481.   Pinus  rigida. 
Old  open  cone  at  the  left. 


used  for  lumber:  leaves  long  and  soft,  light  green,  in  5's:  cones  long  and 

symmetrical,   with  thin-edged  scales,  terminal  on  the  shoots  and  falling 

after  shedding  the  seeds.    Grows  as  far 

south  as  Georgia. 

P.  palustris,  Mill.    Long-leaved  pine. 

Very  tall  tree,  with  nearly  smooth  hark: 

leaves  very  long  and  slender   (usually  a 

foot  or  more),  clusters  at  the  ends  of  the 

branches,    in    3's:    cones    6    in.   or   more 

long,  the    scales    tipped    with    a    short 

curved    spine.     Lumber    tree.     Virginia, 

south. 

P.  rigida,  Mill.    Pitch  pine.   Fig.  481. 

Medium-sized  or  small   tree  with  rough 

dark  bark:  leaves  short  and  stiff,  usually 

in   3's:    cone   2-3    in.    long,    conical,  the 

scales  with  a  short  spine.     Grows  as  far 

south  as  Virginia;  common  in  pine  barrens  of  the  north  Atlantic  coast. 

eastern  species. 

P.  sylvestris,  Linn.   Scotch  pine.  Fig.  482.   Medium-sized  tree,  with  glau- 
cous green  leaves  in  2's:  cone  short,  the  scales  tipped  with  a  prickle  or  point. 

Europe;  very  commonly 
planted. 

P.  austriaca,  Hoss. 
Austrian  pine.  Fig.  482. 
Large  tree  with  rough 
bark,  and  long,  dark 
green  stiff  leaves  (about 
6  in.  long)  in  2's:  cone 
about  3  in.  long,  ■  the 
scales  not  prickly. 
Europe,  commonly 
planted;  a  coarser  tree 
Pinus  sylvestris  (left).    Pinus  austriaca.  than  the  Scotch  pine. 


An 


2.  PICEA.    Spkuci 


Trees  of  medium  or  large  size,  with  short,  scattered  leaves:  cones 
maturing  tin1  first  year,  hanging  at  maturity,  their  scales  thin. 

P.  Abies,  Karst.  (P.  excelsa,  Link).  Norway  spruce.  Figs.  297,  298. 
Becoming  a  tall  tree:  cones  5-7  in.  long,  the  large  scales  very  thin-edged. 
Europe,  but  the  commonest  of  planted  evergreens.  Until  25-40  years  "Id. 
the  trees  are  symmetrical  cone-shaped  /*A<V  S>i6£&-£'1>~  ' '  '■'■ 

specimens,     holding     their     lower  //A^W^^^^^vA^-V 

branches.  S&^l^ 

P.    mariana,    B.S.P.     (P.    nigra,   f  ^tft 

Link).   Black  spruce.  Fig.  4S3.  P.ccom-  483.    Picea  mariana. 


326 


THE    KINDS    OF    PLANTS 


ing  a  middle-sized  tree,  with  dull,  dark  foliage;  cones  \]4  in.  or  less  long, 
usually  hanging  for  several  years,  the  edges  of  the  scales  often  irregular. 
Cold  woods,  as  far  south  as  North  Carolina  in  the  mountains. 

3.  TSUGA.    Hemlock  Spruce. 

Differs  from  Picea  in  having 
flat  2-ranked  petioled  leaves:  cones 
hanging  on  the  end  of  last  year's 
branches. 

T.  canadensis,  Carr.    Hemlock. 
Fig.  484.    Large  forest  tree,  with 
484.    Tsuga  canadensis,  deep-furrowed,     dark     bark    and 

coarse  wood:  leaves  whitish  be- 
neath: cones  not  an  inch  long,  compact.  Common  lumber  tree.  Bark  much 
used  in  tanning. 

4.  LARIX.    Larch. 

Trees  of  medium  size:  leaves  soft,  short,  in  fascicles  or  clusters  on 
short  branchlets,  falling  in  autumn:  cones  much  like  those  of  Picea,  but 
standing  erect  at  maturity. 

L.  decidua,  Mill.  (L.  europcea,  DC).  European  larch.  Leaves  1  in. 
long:  cones  of  many  scales,  about  1  in.  long.  Planted  for  ornament  and 
timber. 

L.  laricina,  Koch  (L.  americana,  Michx.).  Tamarack.  Hackmatack. 
Leaves  shorter  and  pale  in  color:  cones  of  few  scales,  Yi  in.  or  less  long. 
Swamps. 

5.  THUJA.    Arborvit^s. 

Trees,  becoming  large:  leaves  opposite,  closely  appressed  to  the  branch- 
lets,  the  latter  frond-like:  cones  small,  oblong  or  globular,  of  few  scales. 
Leaves  awl-like  on  new  growths  and  scale-like  on  the  older  growths. 

T.  occidentalis,  Linn.  Arborxitaz.  White  cedar  of  some  places.  Fig. 
485.  Cones  J^  in.  or  less  long,  bearing  2-winged  seeds.  Swamps  and  cold 
woods,  as  far  south  as  North  Carolina  in 
the  mountains.  Very  commonly  planted 
as  a  hedge  evergreen  and  as  single  speci- 
mens, but  in  the  wild  becoming  very  large 
trees  and  much  used  for  telegraph  poles. 


485.    Thuja  occidentalis. 


6.   JUNIPERUS.    Juniper. 

Small  trees  or  shrubs,  with  opposite 
or  whorled  awl-like  leaves  (often  of  two 
kinds) :  fertile  catkin  of  3-6  fleshy  scales 
which  cohere  and  form  a  berry-like  fruit  containing  1-3  hard  seeds. 

J.  communis,  Linn.  Common  juniper.  Shrub,  erect  or  usually  spreading 
and  lying  close  to  the  ground,  with  leaves  in  whorls  of  3  and  all  alike  (awl- 
like): berries  large  and  smooth.    Banks  and  sterile  ground. 


THE     AEUMS  327 

J.  virginiana,  Linn.  Red  cedar.  Savin.  Small  tree  or  largo  shrub, 
usually  narrow  pyramidal  in  growth,  with  leaves  of  two  kinds  (scale-like 
and  awl-like,  the  former  small  and  lying  close  to  the  branch):  berry  glaucous: 
heart-wood  red  and  highly  scented.    Common  on  banks  and  in  old  fields. 


BB.      ANGIOSPERMS:   C.  MONOCOTYLEDONS. 

III.  ARACE.E.   Arum  Family. 

Perennial  herbs,  with  rhizomes  or  corm-like  tubers  and  acrid  juice: 
flowers  minute,  often  diclinous  and  naked,  borne  on  a  spadix  and 
surrounded  or  attended  by  a  spathe:  fruit  usually  a  berry,  the  entire 
spadix  usually  enlarging  and  bearing  the  coherent  berries  in  a  large 
head  or  spike.  Leaves  often  netted-veined.  Mostly  tropical  plants, 
and  some  of  temperate  regions,  many  of  them  odd  and  grotesque. 
Genera  about  100;  species  about  1,000.  Representative  plants  are 
skunk  cabbage,  jack-in-the-pulpit,  calla,  caladium,  anthurium. 

a.   Leaves  compound 1.  Arissema 

aa.  Leaves  simple. 

B.  Spathe  hooded  or  roofed  at  the  top 2.  Symplocarpus 

BB.   Spathe  open  or  spreading  at  the  top 3.  Riehardia 

bbb.  Spathe  open  and  spreading  for  its  whole  length 4.  Calla 

bbbb.  Spathe  separated  from  spadix,  appearing  lateral. .  .  .5.  Acorus 

1.  ARISSEMA.    Indian  Turnip.    Jack-in-the-Pulpit. 

Stem  arising  from  a  corm-like  tuber,  and  bearing  1  or  2  compound  leaves 
with  sheathing  petioles:  flowers  naked  and  diclinous,  the  pistillate  at  the 
base  of  the  spadix  and  the  staminate  above  them  (or  the  plant  dioecious), 
the  top  of  the  spadix  not  flower-bearing:  staminate  flowers  of  a  few  sessile 
anthers,  and  the  pistillate  with  1  sessile  ovary,  which  ripens  into  a  red  few- 
seeded  berry.  Plants  of  spring  or  early  summer,  in  rich  woods.  Tuber 
very  pungent,  often  used  in  domestic  medicine. 

A.  triphyllum,  Schott.  Jack-in-the-pulpit.  Common  Indian  turnip. 
Fig.  251.  Leaves  usually  2,  each  bearing  3  oblong  elliptic  pointed  leaflets: 
spathe  purple-striped,  curving  over  the  spadix. 

A.  Dracontium,  Schott.  Dragon-root.  Leaf  usually  1,  with  7-11  narrow 
oblong  leaflets:  spathe  greenish,  shorter  than  the  spadix. 

2.  SYMPLOCARPUS.   Skunk  Cabbage. 

Leaves  and  flowers  arising  from  a  strong  rootstock,  the  Ivs.  very  large 
and  appearing  after  the  spathes:  fls.  perfect,  each  with  4  sepals,  4  stamens 
and  single  ovary  which  is  sunk  in  the  fleshy  spadix:  fruit  made  up  of  the 
fleshy  spadix  with  imbedded  fleshy  seeds:  spathe  pointed  and  arching,  in- 
closing the  spadix.    Common  in  wet  meadows  in  the  northeastern  states. 


328 


THE    KINDS    OF    PLANTS 


S.  fcetidus,  Nutt.  Spathes  purple,  arising  in  the  earliest  spring:  leaves 
very  large  (often  2  ft.  long),  simple  and  entire,  ovate,  in  tufts.  The  tufted 
leaves  and  fetid  odor  give  the  plant  the  name  of  skunk  cabbage. 

RICHARDIA.   Calla  Lily. 

Leaves  several  from  each  short  rootstock,  their  pe- 
tioles sheathing  the  flower-scape:  flowers  naked  and 
diclinous,  the  stamens  above  and  the  3-loculed  ovaries 
below  on  the  spadix:  spathe  large  and  showy,  the  top 
flaring  and  the  base  rolling  about  the  spadix.  Several 
species  are  cultivated,  but  the  following  is  the  only  com- 
mon one. 

R.  africana,  Kunth.    Calla  or  Calla  lily  of  gardens. 
Fig.  486.    Leaf-blades  broadly  arrow-shaped,  simple  and 
entire,  cross-veined,  glossy:  spathe  white  and  wax-like. 
Cape   of   Good    Hope. 


n 

486.    Richardia 
africana. 


4'  CALLA.    Water  Arum. 

Differs  from  the  above  in  having  a  spathe  which  does  not  inclose  the 
spadix,  and  mostly  perfect  flowers  (the  upper  ones  sometimes  staminate), 
each  of  6  stamens  and  1  ovary:  fruit  a  red  berry.    One  species. 

C.  paliistris,  Linn.  True  calla.  Fig.  487.  Leaves  about  1  ft.  high,  the 
blades  arrow-shaped:  spathe  about  2  in.  long,  white  on  the  upper  face. 
In  cold  bogs,  north. 

5.  ACORUS.   Sweet  Flag.    Calamus. 

Erect,  having  long,  horizontal,  branching  root-stocks,  thick  and  aromatic : 
leaves  sword-shaped,  rising  from  the  rootstocks:  scapes  3-angled,  bearing 
each  a  cylindric  spadix,  but  much  prolonged  and  leaf-like,  causing  the 
spadix  to  appear  as  if  borne  on  the  side  of  the  leaf -like  scape:  flowers  on  a 
very  dense  spadix:  ovary  oblong,  2-4-celled,  with  2-8 
ovules  in  each  cell. 

A.  Calamus,  Linn.  Sweet  flag.  Calamus-root.  Along 
the  margins  of  streams,  in  swamps  and  wet  soils. 
Leaves  2-3  ft.:  flowers  greenish-yellow,  very  small. 
May  to  July.  The  rootstocks  supply  "sweet  flag  roots" 
of  the  druggists. 

IV.  LILIACE^E.   Lily  Family. 


Herbs,  with  bulbs,  corms,  or  large  rootstocks: 


fls.  mostly  regular  and  showy,  the  perianth  of  6 
separate  or  coherent  parts,  the  stamens  usually  6  and  standing  in  front 
of  the  parts  of  the  perianth:  ovary  superior,  usually  3-loculed,  ripen- 
ing into  a  capsule  or  berry.    About  200  genera,  including  more  than 


LILY    FAMILY  329 

2,000  widely  distributed  species.  Characteristic  plants  are  lily,  lily-of- 
the-valley,  onion,  Solomon's  seal,  tulip,  trillium,  hyacinth,  asparagus, 
yucca. 

a.  Fruit  a  LoculicidaJ  capsule. 
B.  Style  1,  undivided. 

c.  Plant  bulbous:  root-leaves  not  in  large  clumps. 

d.  Stem  tall  and  leafy 1.  Lilium 

dd.  Stem  short,  with  only  2-6  leaves. 

e.  Flower  erect 2.  Tulipa 

ee.  Flower  nodding 3.  Erythronium 

ddd.  Stem  naked,  bearing  many  flowers. 
e.  Perianth  tubular. 

F.  Flowers  funnelform,   throat  open:     lobes 
spreading  or  recurved,    as  long  as   the 

tube 4.  Hyacinthus 

ff.  Flowers  urn-shaped,  constricted  at  throat; 

lobes  much  shorter  than  tube 5.  Muscari 

ee.  Perianth  parted  nearly  to  base 6.  Orniihogalum 

cc.  Plant   with   a   rootstock,    and   large   clumps   of 
leaves. 
d.  Flowers  yellow  and  paniculate  on  a  somewhat 

branching  scape 7.  Hemerocallis 

dd.  Flowers   white   or   blue,    mostly   in    a   simple 

raceme 8.  Fun  I:  in 

bb.  Style  1  at  base,  but  3-cleft  or  3-parted:  flowers 

bell-like,  drooping,  yellow 9.  Uvula ria 

aa.  Fruit  an  angled  berry:  styles  or  stigmas  3:  leaves 

broad  and  netted-veined 10.  Trillium 

aaa.  Fruit  a  globular  berry:  style  1:  fls.  small  white,  or 
greenish. 
b.   Foliage  made  up  of  cladophylls,   tin-   true   leaves 
being  mere  scales:   stamens   borne   on   the   base 

of  the  small  corolla 11.  Asparagus 

bb.  Foliage  of  ordinary  leaves:  stamens  borne  on  the 
corolla-tube. 

c.  Perianth  of  6  parts,  separate 12.  Smilacina 

cc.  Perianth  of  4  parts 13.  Maiantfu  mum 

ccc.  Perianth  gamosepalous,  with  6  lobes. 

d.  Flowers  racemose  on  a  scape 14.  Coitvallariu 

dd.  Flowers  hanging  from  the  axils  of  the  leaves..  15.  Polygonatum 

1.  LILIUM.    Lily. 

Strong-growing  bulbous  herbs,  with  leafy  stems  usually  bearing  several 
or  many  Sowers:  perianth  bell-shaped  or  funnelform,  the  <>  divisions  nearly 
nr  quite  separate  and  spreading  or  recurving  and  having  a  honey-bearing 
groove  at  the  base:  anthers  attached  by  the  middle  (versatile). 


330 


THE    KINDS    OF    PLANTS 


a.  Flowers  white. 

L.  longiflorum.  Thunb.  Easter  lily.  One  to  4  ft.,  with  scattered  long- 
lanceolate  pointed  leaves:  flowers  5-8  in.  long,  horizontal,  scarcely 
widened  from  the  base  to  the  middle,  fragrant.  Japan  and  China,  now 
much  cultivated  under  glass.  Many  of  the  bulbs  are  grown 
^\^  jftuTTi  *n  *^e  Bermuda  Islands,  whence  the  name  "Bermuda  lily." 
L.  candidum,  Linn.  Common  white  lily.  Leaves  broad- 
lanceolate,  scattered:  flowers  numerous,  5  in.  or  less  long, 
widening  gradually  from  the  base.  Europe.  Common  in 
gardens. 


Lilium 
philadelphicum. 


aa.  Flowers  in  shades  of  yellow  or  orange. 

L.  philadelphicum,  Linn.  Fig.  488.  Flowers  1-3,  erect, 
2-3  in.  long,  orange-red  and  spotted,  the  divisions  separate: 
leaves  whorled.    Dry  soil. 

L.  canadense,  Linn.   Wild  orange-red  lily.  Wood  lily.  Two 
to  5  ft.,  with  leaves  in  whorls  and  bulbs  producing  rhizomes 
or  runners:  fls.  several  or  many,  erect  or  horizontal  on  long 
stalks,  the  divisions  spreading  above  the  middle,  orange  or 
red  and  spotted.    Meadows  and  swales. 

L.  superbum,  Linn.  Turk's-cap  lily.  Fig.  489.  Very  tall, 
bearing  several  or  many  nodding  red-orange  spotted  flowers 
in  a  panicle,  the  segments  all  pointing  backward.  Meadows 
and  low  grounds. 

L.  tigrinum,  Ker.  Tiger  lily.  Fig.  31.  Four  to  5  ft., 
bearing  a  loose  cottony  covering  on  the  stems:  leaves  sessile, 
scattered,  lanceolate:  flowers  many,  nodding  in  a  panicle, 
orange-red  and  black-spotted,  the  divisions  about  4  in.  long 
and  rolled  back.    China  and  Japan;  old  gardens. 

2.  TULIPA.    Tulip. 

Low  bulbous  plants  with  a  few  leaves  near  the  ground  on  the  1-flowered 
stem:  flower  large,  erect,  the  6  divisions  erect  or  flaring:  capsule  triangular. 
T.   Gesneriana.     Linn.     Common  tulip.    Leaves  3-6,  broad:  peduncle 
glabrous:  divisions  of  the  flower  broad  at  the  end,  with  a 
very  short  point  in  the  center:  late-blooming  tulips,  orig- 
inally from  Asia  Minor. 

T.  suaveolens,  Roth.  Due  Van  Thol  tulip.  Early  and 
dwarf,  with  fewer  leaves,  downy  peduncle,  and  acuminate 
segments.    Caspian  Sea;  common  in  cultivation. 

3.  ERYTHRONIUM.   Dog's-tooth  Violet. 

Low  herbs  with  deep-seated  conical  bulbs,  and  scape 
with  2  leaves  near  the  ground:  flower  nodding,  the  6  divi- 
490.  Erythronium    sions  wide-spreading  or  recurved,  the  style  long  and  club- 
americanum.       shaped.    Blooming  in  earliest  spring. 


LILY    FAMILY  331 

E.  americanum,  Smith.  Common  dog's-tooth  violet,  or  adder' s-tongue. 
Fig.  490.  Leaves  thickish,  oblong-lanceolate,  mottled  with  purple:  flower 
light  yellow,  nodding  on  a  stem  3-6  in.  tall.    Low  grounds. 

E.  albidum,  Nutt.  White  adder' s-tongue.  Leaves  scarcely  mottled: 
flowers  whitish.    Low  grounds. 

4.  HYACINTHUS.    Hyacinth. 

Low  plants,  with  large  bulbs,  producing  many  flowers  in  spikes  or  dense 
racemes  on  a  short  scape,  the  leaves  arising  directly  from  the  bulb:  flowers 
bell-shaped  or  funnelform,  the  6  lobes  spreading  or  curling  back. 

H.  orientalis.  Linn.  Common  hyacinth.  Fig.  186.  Early  spring,  the 
flowers  of  many  colors  and  sometimes  double,  the  perianth-tube  swollen, 
the  oblong-spatulate  lobes  as  long  as  the  tube.    Greece  to  Asia  Minor. 

Var.  albulus,  Baker.  Roman  hyacinth.  Flowers  fewer  and  usually 
smaller,  white  or  nearly  so,  the  perianth-tube  scarcely  swollen  and  the  lobes 
shorter.    France.    Much  cultivated. 

5.  MUSCARI.    Grape  Hyacinth. 

Low  herbs,  with  very  narrow,  somewhat  fleshy  leaves  and  small  flowers 
in  a  raceme:  perianth  deep  blue  or  white,  the  tube  ventricose  or  urn-shaped, 
with  6  short  blunt  teeth. 

M.  botryoides.  Mill.  Grape  hyacinth.  Flowers  faintly  odorous,  nod- 
ding, deep  blue:  scape  4-10  in.:  leaves  linear,  obtuse,  erect,  becoming  longer 
than  scapes.  In  grass  about  gardens  and  lawns  in  very  early  spring;  also 
escaped  in  some  places  to  meadows  and  along  roadsides.    Asia. 

6.  ORNITHOGALUM.   Star  of  Bethlehem. 

Stemless  low  herbs,  with  narrow  linear,  fleshy,  channelled  leaves: 
flowers  in  terminal  clusters,  usually  with  conspicuous  bracts:  perianth 
of  (i  parts,  white,  spreading,  veined:  stamens  6,  hypogynous:  filaments 
flattened,  subulate:  ovary  sessile,  3-celled:  capsule  roundish,  3-angled: 
seeds  few,  black. 

O.  umbellatum.  Linn.  Scape  4-10  in.;  flowers  5-8,  on  long  spreading 
pedicels:  sepals  white,  each  with  green  band  outside.  Common  about 
gardens.    Introduced  from  Europe.    Early  spring. 

7.  HEMEROCALLIS.    Day-lily. 

Strong-growing  plants  from  tuberous  roots,  producing  clumps  of  long 
swoid-shapcd  leaves:  flowers  yellow  or  orange,  erect,  large  and  lily-like,  in 
clusters  or  panicles  on  a  tall,  branching  scape,  the  divisions  widely  spread- 
ing at  the  top.    Old  World,  but  common  in  gardens. 

H.  ffilva,  Linn.  Orange  day-lily.  Flowers  tawny  orange,  produced  in 
early  summer,  the  inner  perianth  divisions  nearly  or  quite  obtuse.  The 
commonest  species,  and  often  escaped  along  roadsides. 

H.  flava,  Linn.  Yellow  day-lily.  Plant  somewhat  smaller,  early- 
blooming:  flowers  fragrant,  pure  lemon-yellow,  inner  divisions  acute. 


332 


THE    KINDS    OF    PLANTS 


491.     Funkia 
subcordata. 


8.  FUNKIA.   White  and  Blue  Day-lily. 

Medium-sized  plants,  producing  dense  clumps  of  broad-bladed  leaves 

from  rootstocks:  flowers  blue  or  white,  in  racemes  on  scapes,  each  flower 

sheathed  at  the  base  by  1  or  2  bracts,  the  perianth-tube  long  and  the  limb 

sometimes  irregular.    China  and  Japan ;  planted  by  houses 

and  along  walks. 

F.  subcordata,  Spreng.  White  day-lily.  Fig.  491.  Leaves 
broadly  cordate-ovate:  flowers  large  and  white,  in  a  short 
raceme,  not  drooping. 

F.  ovata,  Spreng.  (F.  casrulea,  Sweet).  Blue  day-lily. 
Fig.  492.  Leaves  broadly  ovate:  flowers  deep  blue,  in  a  long 
raceme,  nodding. 

9.  UVULARIA.   Bellwort.    "Wild  Oats." 

Low,  erect  plants,  with  short  rootstocks:  stems  with 
leaves  alternate  above,  sessile  or  perfoliate,  parallel-veined: 
flowers  yellow,  drooping,  solitary  at  the  end  of  the  forking 
stems,  the  perianth  elongated,  bell-shaped,  of  6  similar, 
distinct,  narrow  sepals,  each  bearing  a  nectar  gland  at  in- 
side base.    Spring-flowering  wood  plants. 

U.  grandiflora,  Smith.  Large-flowered  Bellwort.  Commonly  1-2  ft. 
tall:  leaves  oblong,  whitish-pubescent  beneath,  and  perfoliate:  perianth 
smooth  on  inner  surfaces.  Common  in  rich  woods.  Blooms  a  little  earlier 
'  than  U.  perfoliate,. 

U.  perfoliata,  Linn.  Smaller  than  the  preceding:  glaucous,  leaves  per- 
foliate: perianth  segments  twisted,  covered  on  inner  surface  with  shining 
grains  (papillose):  flowers  somewhat  fragrant,  pale 
yellow.     Common  in  moist  woods. 

U.  sessilifolia,  Linn.  (Oakesia  sessilifolia) .  Straw 
lily.  Leaves  sessile,  lance-oval,  thin,  smooth,  pale  be- 
neath: stem  angled,  slender  and  zigzag:  flower  green- 
ish-yellow, about  1  in.  long.    Woods. 

10.  TRILLIUM.   Wake-robin. 

Low  herbs  from  deep-seated  corm-like  tubers: 
leaves  3  in  a  whorl,  broad  and  netted-veined :  flower 
single,  of  3-colored  petals  and  3  green  sepals,  the 
latter  persistent  until  the  angled,  many-seeded  berry 
ripens;  stigmas  3,  often  sessile.  Plants  of  earliest  spring,  growing  in 
rich  woods. 


492.    Funkia  ovata. 


a.  Flower  sessile  in  the  leaf-whorl. 


T.  sessile,  Linn.  Flowers  dull  purple,  the  parts  narrow,  pointed,  and 
nearly  erect:  leaves  sessile,  ovate,  often  blotched  with  purple.  Pennsylvania, 
west  and  south. 


LILY    FAMILY  333 

aa.  Flower  stalked  in  the  leaf-whorl. 

T.  grandiflorum,  Saliab.  Common  wake-robin,  or  birthrool.  Fig.  244. 
Flowers  large  and  white,  the  peduncle  standing  erect  or  nearly  so,  the 
petals  broadest  above  the  middle  (obovate)  and  2-23^  in.  long:  leaves  broad- 
ovate,  sessile  or  nearly  so.    Flowers  become  rose-pink  with  age. 

T.  erectum,  Linn.  Flowers  smaller,  ill-scented,  varying  from  white  to 
pink  and  purple,  the  peduncle  erect  or  declined,  the  petals  ovate  or  lanceo- 
late and  spreading:  leaves  broad-ovate.  Frequent  North,  and  south  to 
Tennessee. 

T.  cernuum,  Linn.  Flowers  not  large,  white,  the  peduncle  declined  under 
the  broad  leaves;  petals  ovate-lanceolate,  rolled  back.    Range  of  the  last. 

T.  undulatum,  Willd.  Painted  wake-robin.  Flowers  on  peduncles 
erect,  or  partly  declined;  segments  ovate,  or  ovate-lanceolate,  margined, 
thin,  widely  spreading,  white,  penciled  with  purple  stripes  at  base;  sepals 
half  as  long  as  petals:  leaves  ovate,  taper-pointed,  distinctly  petioled, 
obtuse  or  rounded  at  the  base.  Cool  damp  woods,  from  New  Brunswick  to 
Georgia,  and  west. 

11.  ASPARAGUS.    Asparagus. 

Mostly  tall,  often  climbing  plants  with  cladophylla  and  very  small 
scale-like  true  leaves:  flowers  white  or  greenish,  small,  bell-shaped,  scat- 
tered or  in  groups  of  2  or  3:  fruit  a  3-loculed  and  1-6-seeded  small  berry. 

A.  officinalis,  Linn.  Common  asparagus.  Figs. 
159,  160.  Erect  and  branchy,  the  strong  young 
6hoots  thick  and  edible:  berries  red.    Europe. 

A.  plumosus,   Baker.    Fig.   161.    Twining,  with 

dark,  frond-like   foliage,    small    white    flowers    and 

black  berries.    South  Africa;  greenhouses. 

493 

A.  medeoloides,  Thunb.    Smilax  of  florists  (but      ,  ",     ,  . , 

.      ,  ,     .       .  .   x     L.       .„.>     rp    .    .  ,  ,.         ,  ,      Asparagus   medeoloides. 

not  of  botanists).    lug.  493.    Twining:  foliage  broad 

and   leaf -like:    flowers  solitary  and  fragrant:    berries  dark  green.     South 

Africa;  much  grown  by  florists. 

12.  SMILACtNA.    False  Solomon's  Seal. 

Low,  erect  plants  with  many  small  white  flowers  in  racemes  or  pani- 
cles: perianth  6-par^ed:  fruit  a  3-loculed  berry:  rootstock  creeping. 

S.  racemosa,  Desf.  False  spikenard.  About  2  ft.  tall,  somewhat  downy, 
with  many  oblong  or  oval  leaves:  flowers  in  a  panicle:  berries  pale  red, 
speckled.    Spring  and  early  summer.    Rich  woods. 

S.  stellata,  Desf.  Nearly  or  quite  smooth:  leaves  narrower:  flowers  in 
a  simple  raceme.    Forms  patches  in  low  ground. 

13.  MAIANTHEMUM.   Two-leaved  Solomon's  Seal. 

Xeat  little  herbs,  with  slender  rootstocks:  stems  unbranched,  few- 
leaved:  flowers  small,  in  an  open  raceme,  with  usually  2  or  3  pedicels 
together;  perianth  of  4  ovate,  obtuse,  spreading  segments,  united  at  base: 
fruit  a  globular  1-2-seeded  berry.    One  species  in  eastern  North  America. 


334  THE     KINDS     OF     PLANTS 

M.  canadense,  Desf.  Slender  stem,  3-6  in.  high,  terminated  by  the 
many-flowered  raceme:  flowers  white:  leaves  ovate,  cordate  at  base,  short- 
stalked.  Common  in  moist  woods  and  on  shaded  banks,  making  mats  or 
patches.    May  to  July. 

14.  CONVALLARIA.    Lily-of-the-valley. 

Low,  spring-flowering  herbs  from  branching  rootstocks:  flowers  gamo- 
petalous,  white  and  waxy,  nodding  in  a  1-sided  raceme,  the  6  short  lobes 
recurving:  fruit  a  red  berry. 

C.  majalis.  Linn.  Leaves  oblong,  numerous  from  the  rootstocks,  form- 
ing mats,  and  about  2  with  each  scape:  flowers  very  fragrant.  One  of  the 
best-known  garden  flowers.    Europe.    The  only  species. 

15.  POLYGONATUM.   Solomon's  Seal. 

Mostly  strong  plants  from  long  running  rootstocks  on  which  the  scars 
of  preceding  stalks  are  very  evident  (whence  the  common  name):  stems 
leafy,  bearing  nodding  gamosepalous  flowers  in  the  axils:  fruit  a  globular, 
dark-colored  berry.    Rich  woods,  spring. 

P.  commutatum,  Dietr.  Three  to  5  ft.  tall:  leaves  ovate,  somewhat  clasp- 
ing: peduncles  in  each  axil,  2-8-flowered:  filaments  not  roughened. 

P.  biflorum,  Ell.  One  to  3  ft.:  leaves  oblong,  nearly  sessile,  somewhat 
glaucous,  hairy:  peduncles  usually  2-flowered:  filaments  roughened. 

V.  COMMELINACEiE.   Spiderwort  Family. 

Herbs,  annual  or  perennial,  with  flat,  narrow  leaves,  sheathing 
at  base:  roots  fibrous,  sometimes  thickened:  flowers  regular  or  irreg- 
ular, perfect,  usually  showy,  in  terminal  cymes,  usually  borne  above  a 
leafy  or  spathe-like  bract;  sepals  3:  petals  3,  soon  decaying  or  falling; 
stamens  6,  hypogynous,  some  of  them  often  deformed  or  abortive: 
ovary  2-3-celled,  style  single,  stigma  entire  or  somewhat  lobed:  juice 
slimy  or  mucilaginous.  More  than  300  species,  mainly  belonging  to 
tropical  regions. 

a.  Flowers    irregular,    inclosed    in    cordate   spathe-like 

floral  leaf;  perfect  stamens  3  (rarely  2) 1.  Commelina 

aa.  Flowers    regular,     or    nearly    so;    bracts    leaf -like; 

stamens  6 2.  Tradescantia 

aaa.  Flowers  somewhat  irregular,  tubular,  usually  in  pairs : 

trailing  habit,  easily  rooting  at  nodes 3.  Zebrina 

1.  COMMELiNA.   Day  Flower. 

Plants  erect  or  partly  procumbent  and  rooting  at  joints,  succulent, 
branching:  leaves  petioled  or  sessile,  the  floral  leaf  or  spathe  cordate: 
flowers  recurved  on  their  pedicels  and  hooded  by  the  floral  leaf  before  and 
after  flowering,  open  for  a  short  time  only. 


SPIDERWORT — AMARYLLIS  335 

C.  virginica,  Linn.  Stem  glabrous  or  somewhat  downy,  ascending  1-2 
ft.:  leaves  Lanceolate  to  linear,  acuminate:  flowers  1  in.  wide,  the  odd  petal 
very  small.    In  moist  soil. 

2.  TRADESCANTIA.    Spiderwort. 

Mucilaginous  herbs,  with  stout,  succulent  stems,  simple  or  branched: 
leaves  elongated,  narrow,  keeled,  sometimes  purple-veined:  flowers  in  ter- 
minal and  axillary  umbelled  clusters,  with  leaf-like  bracts,  not  tubular; 
filaments  glabrous  or  bearded. 

T.  virginiana,  Linn.  Plant  green,  erect,  with  linear  leaves:  flower- 
clusters  showy,  terminal;  corolla  over  1  in.  broad,  the  3  petals  deep  blue 
(rarely  white),  longer  than  sepals;  filaments  blue,  and  clothed  with  hairs. 
Cultivated  and  wild;  mostly  in  rich  soil.  Very  variable.  Flowers  quickly 
fading  by  becoming  mucilaginous,  but  produced  all  summer. 

T.  pilosa,  Lehm.  Stout,  more  or  less  zigzag,  stems  soft-hairy  or  nearly 
smooth:  leaves  lanceolate,  tapering  at  apex,  narrowed  at  base,  hairy  on  both 
sides:  cymes  terminal  and  axillary,  or  on  short  axillary  branches:  flowers 
%-\  in.  wide.    In  rich  moist  soil,  woods  and  thickets,  or  in  shaded  places. 

T.  fluminensis,  Veil.  One  of  the  greenhouse  plants  known  as  Wandering 
Jew  (see  Zebrina),  but  leaves  usually  green  and  flowers  white.  South  America. 

3.  ZEBRINA.    Wandering  Jew. 

Low,  trailing  or  partially  climbing,  rooting  readily  at  the  nodes,  and 
branching:  leaves  often  striped  with  purple,  green,  white,  thick  and  ovate: 
flowers  small,  more  or  less  irregular,  tubular,  usually  in  pairs. 

Z.  pendula,  Schnitzl.  Stems  trailing,  perennial:  corolla  3-parted, 
roseate:  calyx  with  short  tube,  3-parted:  ovary  3-celled,  3-6  ovuled:  leaves 
ovate  or  oblong,  heavy  or  succulent,  green  and  silver  stripes  above,  purple 
beneath.    Much  used  for  vases  and  baskets.    A  native  of  Mexico. 

VI.  AMARYLLIDACE.E.   Amaryllis  Family. 

Differs  from  Liliacese  chiefly  in  having  an  apparently  inferior  ovary 
and  in  bearing  its  flowers  more  uniformly  on  scapes.  More  than  600 
species  in  nearly  70  genera,  widely  dispersed.  Representative  plants 
are  narcissus,  daffodil,  snowdrop,  tuberose,  amaryllis.  Plants  of 
the  first  three  genera  may  be  grown  from  bulbs  in  the  school-room. 

A.    Plants  from  coated  bulbs;  stem  a  leafless  scape 

B.   Perianth  with  a  crown  or  cup  in  its  center 1.  Narcissus 

bb.  Perianth  with  no  cup. 

c.   Anthers  and  style  pointed 2.  Gala?ithus 

cc.  Anthers  and  style  blunt 3.  Leucoium 

aa.  Plants  from  tuberous  rootstocks  or  corms. 

B.  Stem  tall  and  leafy 4.  Polianthes 

bb.  Stem  a  low,  leafless  scape 5.  Hypoxis 


336 


THE     KINDS     OF     PLANTS 


1.  NARCISSUS.    Narcissus.    Daffodil. 

Low  plants  producing  from  1  to  many  6-parted  flowers  on  a  scape  which 
arises  from  a  tunicated  bulb:  perianth  with  a  long  tube  and  bearing  a  cup 
or  crown  in  its  center.     Old  World,   but   frequently 

CiHs^V  cultivated. 

AC      . 

<ju m     inw  ,-"^jb  a-  Crown  as  long  as,  or  longer  than,  the 

divisions  of  the  perianth. 

N.  Pseudo-Narcissus,  Linn.  Trumpet  narcissus. 
Common  daffodil.  Scape  1-flowered,  the  flower  large 
and  yellow  with  a  relatively  short  tube  and  a  wavy- 
edged  crown.  Leaves  flat  and  glaucous.  Double  forma 
are  common  in  gardens. 


494. 
Narcissus  Tazetta. 


Crown  half  or  more  as  long  as  the  divisions 
of  the  perianth. 


N.  incomparabilis,  Curt.  Scape  1-flowered,  the  flower  about  2  in.  or 
more  across,  yellow,  the  cylindrical  tube  1  in.  long,  the  crown  plaited  and 
usually  a  deeper  yellow:  leaves  flat  and  glaucous. 


aaa.   Crown  less  than  half  the  length  of  the  division. 

N.  Tazetta,  Linn.  Polyanthus  narcissus.  Chinese  sacred  lily.  Fig.  494. 
Flowers  several  to  many  in  an  umbel,  yellow  or  white,  small,  the  crown 
usually  darker  colored  and  usually  somewhat  scalloped:  leaves  flat  and 
somewhat  glaucous.  One  of  the  commonest  kinds.  The  narcissus  known 
to  florists  as  "Paper-white"  is  a  white-flowered  form  of  this 
species. 

N.  poeticus,  Linn.  Poet's  narcissus.  Scape  rather  slender, 
usually  1-flowered,  the  flower  white  with  the  thick  rim  of 
the  very  short  crown  margined  with  red:  leaves  flat,  glaucous. 

N.  Jonquflla,  Linn.  Jonquil.  Scape  2-5-flowered,  the 
flowers  small  and  yellow,  the  tube  slender  and  the  segments 
wide-spreading:  leaves  linear,  somewhat  cylindrical. 

2.  GALANTHUS.    Snowdrop. 

Small,  spring-blooming  plants,  with  a  single  white  flower 
nodding  from  the  top  of  the  scape,  followed  by  grass-like 
leaves:  perianth  divisions  6,  oblong  and  more  or  less  con- 
cave, the  three  inner  ones  shorter,  some  of  them  usually 
green-blotched  at  the  tip;  anthers  and  style  pointed. 

G.  nivalis,  Linn.  Snowdrop.  Fig.  495.  One  of  the  earliest  of  spring 
flowers,  appearing  as  soon  as  the  snow  is  gone,  the  flower  and  leaves  arising 
from  a  small  bulb:  scape  6  in.  or  less  high:  inner  divisions  of  the  bell-shaped 
flower  tipped  with  green.    Europe. 


495.    Galanthua 
nivalis. 


IRIS    FAMILY  337 

3.  LEUCOIUM.    Snowflake. 

Flowers  often  more  than  1:  divisions  of  the  perianth  all  alike:  anthers 
and  style  blunt:  otherwise  very  like  Galanthus. 

L.  vernum,  Linn.  Snowflake.  Taller  than  the  snowdrop  (about  1  ft.), 
the  scape  usually  1-flowered,  blooming  later,  the  flowers  larger.    Europe. 

4.  POLIANTHES.    Tuberose. 

Leafy-stemmed  lily-like  plants,  with  a  thick,  tuberous  rootstock  (whence 
the  name  tuber-ose  not  tube-rose),  bearing  an  erect  spike  of  white  flowers; 
perianth  with  a  short  slightly  curved  tube  and  6  spreading  nearly  equal 
divisions:  stamens  included  in  the  tube  (not  projecting). 

P.  tuberosa,  Linn.  Tuberose.  Two  to  3  ft.,  bearing  long-linear,  chan- 
nelled, many-ranked  leaves:  flowers  very  fragrant,  sometimes  tinted  with 
rose.  A  popular  garden  plant  from  Mexico,  blooming  in  the  open  in  late 
summer  and  autumn;  some  forms  are  double. 

5.  HYPOXIS.    Star-grass. 

Stemless,  with  grass-like,  hairy  leaves,  growing  from  a  corm-like  root- 
stock:  flowers  yellow  on  filiform  scapes;  perianth  6-parted. 

H.  hirsuta,  Coville.  Scape  3-8  in.,  not  so  long  as  the  grassy  leaves,  soft- 
hairy:  flowers  1-4,  yellow,  greenish  without,  about H  in.  in  diameter.  Com- 
mon in  dry  soils. 


VII.  IRIDACE^.    Iris  Family. 

Differs  from  Amaryllidacese  and  Liliacese  in  its  inferior  ovary, 
3  stamens  which  are  opposite  the  outer  parts  of  the  perianth,  and 
2-ranked  equitant  (bases  overlapping)  leaves:  stigmas  sometimes  large 
and  petal-like.  About  60  genera  and  700  species.  Representative 
plants  are  iris  or  blue  flag,  crocus,  gladiolus,  freesia.  Crocuses  and 
freesias  are  easily  grown  in  window-boxes  for  winter  and  spring  bloom. 

a.  Lobes  of  the  style  expanded  and  colored,  looking  like 

petals 1.  Iris 

AA.   Lohes  of  the  Style  thread-like. 

B.  Plant  stemless:  flowers  borne  on  scapes. 

c.   From     corms:     spathe     1-flowered:     flower     large, 

and  perianth-tube  long  and  slender 2.  Crocus 

cc.  From  mostly  fibrous  roots:  perianth-tube  scarcely 
perceptible,  if    at  all:     flowers  small:    spathe  2- 

or  more  flowered 3.  Sisyrinchium 

bb.  Plants  with  a  leaf-bearing  and  flower-bearing  stem. 

c.  Flowers  in  a  short  1-sided  cluster:  plant  small 4.  Freesia 

cc.  Flowers  in  a  terminal  spike:  plant  large 5.  Gladiolus 

V 


338 


THE     KINDS     OF     PLANTS 


496.   Iris  germanica. 


1.  IRIS.    Fleur-de-lis.    Flag. 

Mostly  strong  plants,  with  rhizomes  or  tubers:  flowers  mostly  large  and 
showy,  the  3  outer  segments  recurving  and  the  3  inner  ones  usually  smaller 
and  more  erect  or  sometimes  incurving;  the  3  long  divisions  of  the  style 
petal-like  and  often  more  or  less  hairy,  covering  the  stamens ;  stigma  on 
the  under  side  of  the  style:  leaves  long  and  sword- 
shaped.  Several  wild  and  many  cultivated  species. 
The  following  species  have  rhizomes: 

a.  Flowers  yellow. 

I.  Pseudacorus,  Linn.  Common  yellow  flag.  One 
to  3  ft.,  with  several-flowered,  often  branching  stems; 
outer  divisions  of  the  perianth  with  no  hairs  or  crests; 
flowers  bright  yellow.    Europe. 

aa.  Flowers  in  shades  of  blue  (sometimes  varying  to  white). 

I.  versicolor,  Linn.  Common  wild  blue  flag.  Two 
to  3  ft.,  stout:  leaves  ?£in.  wide,  flat:  flowers  about  3 
in.  long,  short-stalked  violet-blue,  the  tube  shorter 
than  the  ovary,  the  inner  petals  small  and  the  outer 
ones  with  no  hairs.  Swamps. 
I.  laevigata,  Fisch.  &  Mey.  (/.  Kacmpferi,  Sieb.).  Japanese  iris.  Two  to 
3  feet,  the  stem  much  overtopping  the  thin,  broad  leaves:  flowers  large 
(sometimes  several  inches  across),  flat,  the  inner  lobes  spreading,  the 
outer  ones  very  large  and  rounded,  with  no  hairs  or  crests:  color  mostly  in 
shades  of  blue  and  purple.  Japan;  now  one  of  the  choicest  of  garden  irises. 
I.  germanica,  Linn.  Common  blue  flag  of  gardens  (sometimes  runs  wild). 
Fig.  496.  Two  to  3  ft,  with  long  sword-shaped  leaves:  flowers  few  or  several 
to  each  stem,  about  3-4  in.  across,  the  drooping  outer  segments  with 
yellow  hairs,  the  inner  segments  erect  and  arching  inward.    Europe. 

2.  CROCUS.    Crocus. 

Small,  stemless  plants,  the  long-tubed  flowers  and  the 
grass-like  leaves  arising  directly  from  the  coated  corm: 
flowers  with  the  6  obovate  divisions  all  alike  and  erect- 
spreading  or  the  inner  ones  a  little  the  smaller,  opening 
only  in  sunshine.  The  following,  from  Europe,  blooms  in 
earliest  spring: 

C.  vernus,  Linn.    Common  crocus.    Fig.  497.    Leaves  ._, 
2-4  to  each  flower,  glaucous  on  the  under  side:  flower 
rising  little  above  the  ground;  color  in  shades  of  lilac  and  variously  striped, 
sometimes  white. 

3.  SISYRINCHIUM.   Blue-eyed  Grass. 

Low,    slender,    perennial    herbs    with    grass-like,    linear,    or    lanceolate 
leaves  and    fibrous  roots:    scapes  or  stems  erect,  compressed,  2-edged  or 


IRIS     FAMILY  339 

winged,  often  branched:  flowers  small,  usually  blue  or  bluish,  soon  wither- 
ing, in  terminal  2-5-flowered  umbels  in  a  2-leaved  spathe;  perianth  seg- 
ments spreading,  bristle-pointed:  stamens  3,  monadelphous;  style  1  long; 
stigmas  very  slender;  ovary  3-celled. 

S.  angustifdlium,  Mill.    Grassy  plants  in  tufts  or  clumps:  scape  4-12  in., 
spathe   single,  sessile:   flowers   blue  to  purple,   rarely 
white;    petals    notched    and    mucronate.      In    moist 
meadows,  among  grass.    Summer.    Common. 

4.  FREfiSIA.    Freesia. 

Small,  cormous  plants  with  flat  leaves:  flowers 
white  or  yellowish,  tubular,  with  a  somewhat  spread- 
ing limb,  the  tube  generally  curved:  stem  about  1  ft. 
high,  bearing  several  erect  flowers  on  a  sidewise 
cluster.  Popular  florists'  plants  of  easy  culture  and 
quick  growth. 

F.    refracta,    Klatt.      Fig.    498.    Leaves    narrow: 
flower  usually  somewhat  2-lipped  or  irregular,  white  in  the  most  popular 
forms  but  yellowish  in  some,  often  with  blotches  of  yellow;  fragrant.    Cape 
of  Good  Hope. 

5.  GLADIOLUS.    Gladiolus. 

Tall,  erect  plants,  with  flat,  strong-veined  leaves,  the  stem  arising  from 
a  corm  (Fig.  54):  flowers  in  a  more  or  less  1-sided  terminal 
spike,  short-tubed,  the  limb  flaring  and  somewhat  unequal: 
stamens  separate  (united  in  some  related  genera):  style 
long,  with  3  large  stigmas. 

G.    gandavensis,    Van   Houtte.     Fig.   499.     Upper  seg- 
ments of  the  perianth  nearly  horizontal:  colors  various  and 
bright:  spikes  long.     Hybrid  of  two  or  more  species  from 
499.     Gladiolus    the  Cape  of  Good  Hope.     Summer  and  fall.    The  common 
gaDdavensis.       gladioli  of  gardens  are  greatly  hybridized. 


VIII.  ORCHIDACE.E.   Orchid  Family. 

Perennial  herbs,  distinguished  by  singular  and  extremely  irregu- 
lar perfect  flowers,  among  the  most  ornamental  and  interesting  of 
native  and  exotic  plants,  curiously  adapted,  in  most  cases,  to  insect 
pollination;  many  air-plants  (epiphytes)  of  the  tropics  and  warmer 
regions  also  belong  to  this  family.  Leaves  visually  alternate,  simple, 
entire,  sheathing:  perianth  in  6  divisions,  adnate  to  the  1-celled  ovary: 
sepals  3,  the  outer  segments  of  the  perianth  usually  colored  and  similar 
or  nearly  so,  appearing  petal-like,  the  2  lateral  petals  generally  alike; 
third  petal,  the  lip  (the  upper  petal  and,  morphologically,  next  to 
axis,  but  apparently  next  to  bract,  by  a  peculiar  twisting  of  the  ovary), 


340  THE     KINDS     OF     PLANTS 

very  unlike  the  others,  usually  larger  and  frequently  lobed,  spurred, 
or  saccate:  stamens  1  or  2  fertile,  variously  coherent  with  the  style 
or  with  a  thick,  fleshy  stigma,  all  together  forming  the  column:  pollen 
in  waxy  or  powdery  masses:  ovary  inferior.  About  5,000  species 
and  over  400  genera,  of  wide  distribution  but  most  abundant  in  the 
tropics;  species  rather  difficult  to  determine,  and  therefore  not  de- 
scribed here  in  detail.  Ours  usually  found  in  cool,  damp  woods,  bogs, 
and  meadows.  Some  of  the  rarest  of  greenhouse  plants,  and  often  very 
difficult  to  grow,  are  members  of  this  family. 

A.  Lip  sac-like  or  inflated,  larger  than  the  other  parts. 
b.  Anthers  2,  one  on  each  side  of  the  style:  a  spread- 
ing sterile  stamen  over  the  summit  of  the  style: 

flowers  generally  large  and  drooping 1.   Cypripedium 

aa.  Lip  not  saccate,  but  spurred,  and  sometimes  fringed: 
flowers  in  a  terminal  spike. 

b.  Sepals  more  or  less  spreading 2.    Hahenaria 

bb.   Sepals  and  petals  somewhat  arching  together 3.  Orchis 

AAA.  Lip  not  noticeably  saccate  or  spurred. 

b.   Flowers  in  spikes,   appearing  more  or  less  twisted 
about  the  spike,  in  1  or  several  rows:  flowers  small. 

•  c.  Leaves  not  variegated 4.  Spiranthes 

cc.  Leaves  variegated  with  white  veins 5.  Epipactis 

bb.  Flowers  1  to  several,  in  a  spike-like  loose  raceme: 
or  terminal  on  a  leaf-bearing  stem. 
a.  Stem  (scape)  from  one  grass-like  leaf:  lip  crested 

with  colored  hairs 6.   Calopogon 

cc.  Stem  1-3-leaved 7.  Pogonia 

1.  CYPRIPfiDIUM.    Lady's  Slipper.    Moccasin  Flower. 

Distinguished  by  having  2  fertile  anthers:  pollen  sticky,  as  though  var- 
nished on  surface,  powdery  beneath:  lip  a  large,  inflated,  spurless  sac, 
toward  which  the  column  bends:  leaves  large,  broad,  many-nerved:  flowers 
large,  showy.    Fig.  250. 

C.  hirsutum,  Mill.  Stem  leafy,  1-2  ft.,  or  more:  flower  solitary  or 
2  or  3  together;  lip  a  globular  sac,  white,  colored  with  purplish-pink.  lM-2 
in.  long.  In  swamps,  bogs  and  woods,  North,  and  South  in  mountains.  June 
to  September.    One  of  our  rare  and  beautiful  wild  flowers. 

C.  acaule,  Ait.  Scape  1  ft.  tall,  with  two  leaves  at  base,  1-flowered: 
sepals  greenish  purple,  spreading;  lip  pink,  veined  with  rose-purple,  about 
2  in.  long,  fragrant,  split  down  the  front,  but  edges  closed.  Woods  and 
bogs.    May  to  June.    Fig.  250. 

C.  pubescens,  Willd.  Stem  slender,  leafy,  1-2  ft.,  usually  clustered, 
1-  to  several-flowered:  flowers  yellow,  lip  much  inflated,  with  purplish  stripes 
or  spots,  lJ^j-2  in.  long.    Low  woods,  meadows.    May  to  July. 

C.  parviflorum,  Salisb.    Stem  1-2  ft.  high,  leafy,  1-  to  several-flowered : 


ORCHIDS  341 

flowers  yellow,  fragrant;  lip  usually  more  marked  with  purplish  spots  or 
lines  than  preceding  and  smaller,  about  1  in.  long.  Low  woods  and  thickets. 
May  to  July. 

C.  candidum,  Muhl.  Lip  white,  with  purple  veins  and  stripes,  not  1  in. 
long.  A  very  rare  species,  found  in  bogs  and  wet  meadows,  New  York  and 
New  Jersey  to  Minnesota,  Missouri,  Kentucky. 

C.  arietinum,  R.  Br.  Slender,  less  than  1  ft.,  leafy  stemmed:  flower  1, 
drooping,  the  3  sepals  separate  and  very  narrow  and  greenish,  the  lip  somewhat 
shorter  than  sepals  Vi  in.  long,  red  with  lighter  veins.    Cold  woods,  North. 

2.  HABENARIA.    Fringed  or  Ragged  Orchids. 

Flowers  several  or  numerous,  in  open  terminal  spikes,  each  flower  in 
the  axil  of  a  foliaceous  bract:  corolla  white,  purplish  or  j'ellow,  with  lip 
variously  fringed  or  3-parted  and  cut-toothed,  spur  longer  than  lip:  1 
anther:  pollen-mass  stalked,  cohering.  Growing,  for  most  part,  in  wet 
places,  borders  of  ponds,  etc.,  through  eastern  United  States.  Several 
species,  rather  too  critical  for  the  beginner  and  therefore  not  described 
here.    By  some,  the  genus  is  broken  up  into  several  genera. 

3.  ORCHIS. 

Very  similar  to  Habenaria,  differing  in  having  the  glands  attached  to 
the  pollen  masses,  and  inclosed  in  a  kind  of  pocket:  the  petals  are  arched  and 
somewhat  connivent  over  the  column. 

O.  spectabilis,  Linn.  Stem  short,  from  2  large  and  glossy  root-leaves, 
and  carrying  1  or  2  lanceolate  bracts,  with  several  flowers  above,  in  a 
raceme:  lip  white,  spurred  at  base:  other  petals  purplish  pink,  arching  up 
over  the  flower.    Woods. 

4.  SPIRANTHES.    Ladies'  Tresses. 

Generally  characterized  by  small  flowers,  whitish,  yellowish  or  greenish 
white,  bent  horizontally  and  arranged  in  1-3  rows  spirally  in  a  spike, 
appearing  as  if  twisted:  stem  usually  bearing  leaves  below,  or  at  the  base: 
lip  of  the  little  flowers  not  saccate  but  erect,  oblong,  recurved,  channelled, 
the  base  embracing  the  column  and  bearing  2  callous  protuberances;  anther 
1-2-celled:  1  powdery  pollen  mass  in  each  cell.    Several  species. 

S.  cernua,  Richard.  Six  to  20  in.  high,  having  leafy  bracts  with  the 
flowers;  spike  dense,  with  flowers  in  3  rows,  inflorescence  appearing  but 
slightly  twisted:  leaves  lance-linear.  Common  in  moist  meadows  and 
swamps.    Late  summer  and  early  autumn. 

S.  gracilis,  Beck.  Spike  and  scape  slender,  with  flowers  in  one  straight 
or  spiral  row:  leaves  all  radical,  ovate  to  oblong,  commonly  withering 
away  at  or  before  flowering.  Common  in  dry  or  sandy  fields,  open  or 
hilly  woods.    July  to  October. 

5.  EPIPACTIS.    Rattlesnake  Plantain. 

In  spike  and  perianth  similar  to  spiranthes,  but  without  the  2  lateral 
callous  protuberances  on  the  lip:  leaves  basal,  tufted,  thickish,  petioled, 


342  THE    KINDS    OF    PLANTS 

dark  green,  usually  blotched  or  veined  with  white.  A  few  species  widely 
distributed,  but  not  common,  with  handsome  leaves.  The  genus  is  also 
known  as  Peramium  and  as  Goodyera. 

6.  CALOPOGON.   Grass  Pink. 

Scapes  from  round  solid  bulbs  bearing  several  flowers  in  loose  terminal 
spikes  or  racemes;  leaf  1,  grass-like.  Distinguished  by  having  the  lip  on 
the  upper  side  (ovary  or  stalk  not  twisting)  bearded. 

C.  pulchellus,  R.  Br.  Scape  1  ft.  high,  2-6-flowered :  flowers  1  in.  across, 
pink-purple;  the  lip  triangular  at  apex,  crested  with  colored  hairs  (yellow, 
orange,  purple),  club-shaped:  anther  lid-like:  pollen-masses  4,  powdery. 
Wet  meadows  and  bogs.    Very  pretty. 

7.  POGONIA. 

Low,  with  solitary,  terminal,  odd  flowers;  alternate  leaves:  lip  spurless, 
crested  or  hooded  or  3-lobed;  column  not  attached:  calyx  spreading;  fertile 
anther  lid-like;  2  pollen-masses,  granular. 

P.  ophioglossoides,  Ker.  Stem  6-9  in.  from  a  fibrous  root;  leaf  sessile, 
oval  near  middle  of  stem:  lip  erect,  bearded  and  fringed;  flower  1  in.  long, 
Bweet-scented,  pale  rose  color,  slightly  nodding,  with  a  leafy  bract.  Marshes 
or  swampy  places.    Eastern  United  States.    June  to  July. 


BB.  PHENOGAMS:  ANGIOSPERMS:  DICOTYLEDONS. 
D.  CHORIPETALM. 

IX.  CUPULlFERiE.   Oak  Family. 

Monoecious  trees  and  shrubs  with  staminate  flowers  in  catkins 
and  the  pistillate  in  catkins  or  solitary:  leaves  alternate,  with  stipules 
early  deciduous  (mostly  scale-like),  and  the  side- veins  straight  or 
nearly  so :  stamens  2  to  many :  fruit  a  1-seeded  nut,  sometimes  inclosed 
in  an  involucre.  Ten  or  a  dozen  genera  and  upwards  of  450  species. 
Representative  plants  are  oak,  chestnut,  beech,  birch,  hazel,  ironwood. 

a.   Sterile  flowers  in  a  hanging  head:  fruits  2  three-cornered 

nuts  in  a  small,  spiny  involucre  or  bur 1.  Fagus 

aa.  Sterile  flowers  in  cylindrical  catkins. 

b.  Fruit  1-4  rounded  or  flat-sided  nuts  in   a  large,  sharp- 
spiny  involucre  or  bur 2.  Castanea 

bb.  Fruit  an  acorn — a  nut  sitting  in  a  scaly  or  spiny  cup 3.  Quercus 

bbb.  Fruit  flat   and   often   winged,   thin   and   seed-like,   borne 
under  scales  in  a  cone. 

c.  Fertile  flowers  naked:  mature  cone-scales  thin 4.  Bctula 

cc.   Fertile  flowers  with  a  calvx:  cone-scales  thick 5.  Alnuh 


BEECH — CHESTNUT — OAK  343 

1.  FAGUS.   Beech. 

Tall  forest  trees  with  light  bark,  and  prominent  parallel  side-veins  in 
the  leaves:  sterile  flowers  in  a  small,  pendulous  head,  with  5-7-cleft  calyx 
and  8-16  stamens:  fertile  flowers  2,  in  a  close  involucre,  ripening  into  2 
three-cornered  "beech  nuts"  in  a  4-valved  bur. 

F.  grandifolia,  Ehrh.  American  beech.  Close-grained,  hard-wood  tree, 
with  light  colored  bark:  leaves  ovate-oblong  and  acuminate,  coarsely  serrate, 
usually  with  9  or  more  pairs  of  nerves:  nuts  ripening  in  the  fall,  and  much 
sought  by  boys  and  squirrels.    A  common  forest  tree. 

F.  sylvatica,  Linn.  European  beech.  Fig.  151.  Often  planted,  particularly 
in  the  form  of  the  purple-leaved  and  weeping  beech:  foliage  differs  in  being 
mostly  smaller,  ovate  or  elliptic,  small-toothed,  with  9  or  less  pairs  of  nerves. 

2.  CASTANEA.    Chestnut. 

Forest  trees,  with  rough,  furrowed  bark:  Sterile  flowers  with 4-7-lobed 
calyx  and  8-20  stamens  in  very  long,  erect  or  spreading  catkins,  which 
appear  in  clusters  in  midsummer:  fertile  flowers  about  3  in  an  involucre, 
producing  "chestnuts"  in  a  spiny  bur. 

C.  dentata,  Borkh.  American  chestnut.  Fig.  267.  Tall,  straight- 
grained  tree,  with  large,  broad  and  thin,  oblong-lanceolate  leaves,  which  are 
taper-pointed,  and  have  large  teeth  with  spreading  spines:  nuts  usually  1  in. 
or  less  across,  sweet.  Grows  as  far  west  as  Michigan,  and  south  to 
Mississippi. 

C.  sativa,  Mill.  European  chestnut.  Less  tall:  leaves  smaller  and 
narrower,  more  pubescent  when  young,  not  long-acuminate,  the  teeth  smaller 
and  their  spines  more  incurved:  nuts  1  in.  or  more  across,  not  so  sweet  as 
those  of  the  American  chestnut.  Europe.  Very  com- 
monly planted. 


I 

500.    Quercus  alba.  501.    Quercus  maerocarpa.  502.    Quercus  Prinus. 

3.   QUERCUS.    Oak. 

Strong,  close-grained  trees,  with  mostly  laterally-lobed  leaves:  sterile 
flowers  in  clustered  hanging  catkins,  with  a  4-7-lobed  calyx,  and  3-12  sta- 
mens: fertile  one  in  a  shallow  involucre  which  becomes  the  cup  of  the 
acorn,  the  stigma  3-lobed:  fruit  an  acorn.  See  Fig.  228,  which  represents 
a  form  of  the  English  oak  {Q.  Robur)  often  planted  in  choice  grounds. 

a.    White  oak  group,  distinguished  by  its  light  gray  scaly  bark,  rounded  lobes 

or  teeth  of  the  leaves,  and  the  acorns  maturing  the  first  year.     (Q.  rin  its 

has  nearly  or  quite  entire  leaves.) 

Q.  alba,    Linn.      White  oak,      Fig.  500.     Leaves    obovate,  5  or  6  in. 

long,  the  Lobes  usually  7  and  al  equal  distances  apart,  and  the  sinuses 


344 


THE     KINDS    OF    PLANTS 


deep  or  shallow:  acorn  small,  with  a  rather  shallow  and  not  fringed  cup. 
The  commonest  species. 

Q.  macrocarpa,  Michx.  Bur  oak.  Fig.  501.  Leaves  obovate,  downy 
or  pale  on  the  lower  surface,  toothed  towards  the  tips  and  irregularly  and 
often  deeply  lobed  toward  the  base:  acorn  cups  heavily  fringed  on  the 
margins:  young  branches  corky.    More  common  West. 

Q.  Prinus,  Linn.    Chestnut  oak.    Fig.  502.    Leaves  rather  long-obovate, 


503.    Quercus  bicolor. 


504.    Quercus  rubra. 


505.    Quercus  coccinea. 


toothed,  with  rounded  teeth  and  yellow-ribbed:  acorn  long  and  the  cup 
hard-scaled:  bark  dark  with  broad,  deep  furrows.    Eastern. 

Q.  bicolor,  Willd.  Swamp  white  oak.  Fig.  503.  Leaves  obovate.  white- 
downy  on  their  lower  surface,  toothed  with  squarish  teeth,  the  bases  wedge- 
shaped:  acorn  small,  with  the  margin  of  the  cup  finely  fringed.  Common 
in  low  grounds  and  along  ravines. 

Q,  virginiana,  Mill.  Live-oak.  Leaves  small,  oblong,  entire  or  sometimes 
spiny-toothed,  thick  and  evergreen:  acorn  oblong,  the  nut  about  one-third 
covered  with  its  scaly  cup.    Virginia,  south. 

aa.   Black  oak  group,  distinguished  by  its  dark  furrowed  bark,  pointed  lobes 
of  the  leaves,  and  the  acor?is  maturing  the  second  year. 

Q.  rubra,   Linn.     Red  oak.     Fig.   504.     Leaves  obovate  or  sometimes 
shorter,  the  7-9  lobes  triangular  and  pointing  toward  the  tips:  acorn  large, 
flat-cupped.    Common. 

Q.  coccinea,  Moench.  Scarlet  oak.  Fig.  505. 
Leaves  obovate,  bright  scarlet  in  autumn,  thin, 
smooth  on  the  lower  surface,  the  sinuses  deep, 
wide  and  rounded :  margin  of  the  acorn  cup  round- 
ing inwards  and  the  scales  close:  inner  bark 
reddish.    Common. 

Q.  veliitina,  Lam.  Black  oak.  Fig.  506. 
Leaves  obovate,  coarser,  downy  on  the  lower  sur- 
face until  midsummer  or  later,  wider  toward  the 
tip,  the  sinuses  shallow  (or  sometimes  as  in  the  scarlet  oak):  margin  of  the 
acorn  cup  not  rounding  inwards  and  the  scales  looser:  inner  bark  orange. 
Common. 

4.  BETULA.    Birch. 

Small  to  medium-sized  trees,  with  sterile  flowers  in  drooping,  cylindrical 
catkins,  3  flowers  with  4  short  stamens  being  borne  under  each  bract:  fertile 


506.    Quercus  velutina. 


BIRCH — ALDER  345 

flowers  in  short,  mostly  erect  cut  kins  which  become  cones  at  maturity,  2  or  3 
naked  (lowers  being  borne  under  each  3-lobed  bract:  fruit  winged  and  seed- 
like: leaves  simple,  toothed  or  serrate;  bark  often  aromatic. 

a.  Brown-barked  birches:  leaves  ovate. 

B.  lenta,  Linn.  Cherry  birch.  Sweet  birch.  Tall  tree,  the  bark  tight 
incit  peeling  in  layers),  the  twigs  very  aromatic:  leaves  oblong-ovate,  some- 
what cordate  at  base,  doubly  serrate,  becoming  glossy  above:  bracts  of  the 
oblong-cylindric  fruiting  catkins  with  wide-spreading  lobes.    Rich  woods. 

B.  lutea,  Miehx.  Yellow  or  gray  birch.  Bark  grayer  or  silvery,  peel- 
ing in  layers:  leaves  scarcely  cordate,  dull,  more  downy:  bracts  of  the 
short-oblong  fruiting  catkins  with  scarcely  spreading  scales:  tree  less  aro- 
matic than  the  other.    Same  range. 

aa.   White-barked  birches:  leaves  triangular  or  broad-ovate. 

B.  papyrifera,  Marsh.  Paper  birch.  Canoe  birch.  Tree  of  medium 
to  rather  large  size,  with  the  bark  peeling  in  very  large  plates  or  layers: 
leaves  broad-ovate  and  often  somewhat  cordate,  dull  green.  Pennsylvania, 
north. 

B.  populifolia,  Ait.  American  white  birch.  Small  and  slender  tree  with 
rather  tight,  glistening,  white  bark:  leaves  triangular-acuminate,  toothed, 
dangling,  and  moving  incessantly  in  the  wind.    Northeastern  states. 

B.  alba,  Linn.  European  white  birch.  A  larger  tree,  with  triangular- 
ovate  leaves  which  are  pointed  but  not  long-acuminate.  Europe.  The  com- 
mon cultivated  white  birch.    There  are  weeping  forms  (Fig.  6). 

5.   ALNUS.    Alder. 

.Much  like  Betula,  but  smaller  trees  or  bushes:  flowers  with  a  3-5- 
parted  calyx,  and  the  small,  short,  fertile  catkins  composed  of  thickened, 
woody  scales.  In  the  following,  the  flowers  appear  before  the  leaves  in 
earliest  spring,  from  catkins  formed  the  previous  year  and  remaining  partly 
developed  during  winter.    Common  along  streams. 

A.  incana,  Moench.  Speckled  alder.  Shrub  or  small  tree,  with  pubescent 
branches:  leaves  oval  to  oblong-ovate,  acute,  doubly  serrate,  glaucous  and 
downy  underneath:  cones  about  }4  in.  long,  mostly  sessile. 

A.  rugosa,  Spreng.  (A.  serruUUa,  Willd.).  Smooth  alder.  Leaves  elliptic 
or  obovate,  acute  or  rounded  at  the  apex,  finely  serrate,  the  under  side 
of  the  leaves  smooth  or  pubescent  only  on  the  veins:  cones  short-stalked. 

A.  vulgaris,  Hill.  Black  alder.  Leaves  orbicular  or  very  broadly  obo- 
vate. not  acute,  irregularly  serrate,  dull  and  nearly  smooth  beneath:  cones 
peduncled.    Europe.    Planted,  some  varieties  with  divided  leaves. 


X.  URTICACE^.    Nettle  Family. 

Trees  and  herbs,  with  small  apetalous  flowers  in  small  clusters  or 
solitary:  leaves  mostly  straight-veined,  with  stipules:  plants  dioecious 
or  monoecious,  or  flowers  perfect  in  the  elms:  stamens  usually  as  many 


346 


THE    KINDS    OF    PLANTS 


as  the  lobes  of  the  calyx  and  opposite  them:  ovary  superior,  ripening 
into  a  1-seeded  indehiscent,  often  winged  fruit.  A  very  polymorphous 
association,  by  some  botanists  divided  into  two  or  three  coordinate 
families.  More  than  100  genera  and  1,500  species.  Representatives 
are  elm,  hackberry,  mulberry,  osage  orange,  nettle,  hop,  hemp. 

a.  Trees. 

b.   Fruit  a  samara 1.  Ulmus 

bb.   Fruit  a  small  drupe 2.  Celtis 

bbb.   Fruit  as  large  as  an  orange,  formed  of  the  whole  mass  of 

the  pistillate  flower-cluster 3.  Madura 

bbbb.  Fruit  resembling  a  blackberry,  formed  of  the  pistillate 

flower-cluster 4.  Morus 

AA.  Herbs. 

b.  Leaves  digitately  lobed  or  divided. 

c.  Plant  standing  erect 5.  Cannabis 

cc.  Plant  twining 6.  Humulus 

bb.  Leaves  not  lobed:  plant  with  stinging  hairs 7.  Urtica 


Ulmus  americana. 


509.    Ulmus  racemosa. 


1.  ULMUS.   Elm. 

Trees,  mostly  large  and  valuable  for  timber,  with  rough-furrowed  bark: 
leaves  alternate  (2-ranked),  ovate  and  straight- veined,  dentate:  flowers  small 
and  not  showy,  appearing  in  earliest  spring,  sometimes  diclinous,  the  calyx 
4-9-parted,  the  anthers  4-9  on  long  filaments:  ovary  generally  2-loculed, 
ripening  into  a  1-seeded  wing-fruit. 


a.  Leaves  large,  rough  on  the  upper  surface:  fruit  large,  nearly  orbicular. 

U.  fulva,  Michx.  Slippery  elm.  Fig.  507.  Middle-sized  or  small  tree 
with  inner  bark  mucilaginous  or  "slippery"  in  spring:  leaves  6-8  in.  long 
and  half  or  more  as  broad,  ovate-elliptic  and  unequal-sided,  doubly 
serrate,  very  rough  above  and  softer  beneath:  samara  H-%  in.  long, 
orbicular  or  nearly  so,  with  the  seed  in  the  center:  flowers  in  dense 
clusters.    Common. 


ELM    TRIBES  347 


aa.   Leaves  not  very  rough  above:  fruit  oval,  deeply  notched  at  the  apex. 

U.  americana,  Linn.  Common  or  white  elm.  Figs.  96-100,  508.  Tall  and 
graceful  tree:  leaves  elliptic-oval,  serrate:  samara  small,  more  or  less  hairy 
on  the  thin  wing,  the  notch  in  the  apex  extending  nearly  to  the  seed:  flowers 
hanging  on  slender  stalks.    One  of  the  finest  of  American  trees. 

U.  racemosa,  Thomas.  Cork  elm.  Fig.  509.  Smaller  tree  than  the  last, 
with  corky-winged  branches:  leaves  with  straighter  veins:  samara  with 
sharp  incurved  points  at  the  apex:  flowers  in  racemes.    Less  common. 

U.  alata,  Michx.  Wahoo  elm.  Small  tree,  with  wide,  corky  ridges  on 
the  branches:  leaves  small  and  rather  thick,  almost  sessile,  ovate  to  nearly 
lanceolate  and  acute:  samara  downy,  at  least  when  young.  Virginia,  south 
and  west. 

2.  CELTIS.    Nettle-tree.    Hackberry. 

Elm-lfke  in  looks,  but  the  fruit  a  1-seeded,  berry -like  drupe:  flowers 
greenish,  in  the  leaf  axils,  mostly  diclinous;  calyx  5-6-parted;  stamens  5  or 
6:  stigmas  2,  very  long. 

C.  occidentalis,  Linn.  Common  hackberry.  Middle-sized  tree  with 
rough-furrowed  bark:  leaves  ovate-pointed,  oblique  at  base,  serrate:  fruit 
purplish,  as  large  as  a  pea,  edible  in  the  fall  when  ripe.    Low  grounds. 

3.  MACLURA.   Osage  Orange. 

Small  tree,  with  dioecious  flowers  in  catkins, 
and  alternate,  simple  leaves:  sterile  flowers  in 
raceme-like,  deciduous  catkins:  fertile  flowers 
densely  crowded  in  a  head,  with  4  sepals  and  2  510.  Madura  pomifera. 
stigmas,  the  ovaryr  ripening  into  an  achene,  the 
whole  flower-cluster  becoming  fleshy  and  ripening  into  an  orange-like  mass. 

M.  pomifera,  Schneid.  (Toxylon  pomiferum,  Raf.).  Osage  orange. 
Fig.  510.  Spiny,  low  tree,  much  used  for  hedges,  but  not  hardy  in  the  north- 
ernmost states:  leaves  narrow-ovate  and  entire,  glossy:  flowers  in  spring 
after  the  leaves  appear,  the  fruit  ripening  in  autumn.  Missouri  and 
Kansas  south. 

4.  MORUS.    Mulberry. 

Small  to  middle-sized  trees,  with  broad,  alternate  toothed  or  lobed 
leaves  and  monoecious  flowers,  with  4-parted  calyx:  stamens  4,  witli  fila- 
ments at  first  bent  inward,  the  staminate  catkins  soon  falling:  fertile  Bowers 
ripening  a  single  achene,  but  the  entire  catkin  becomes  fleshy  and  blackberry- 
like, and  prized  for  eating.  Leaves  very  variable,  often  lobed  and  not 
lobed  on  the  same  branch. 

M.  rubra,  Linn.  Common  wild  mulberry.  Often  a  large  tree  in  the 
South:  leaves  ovate-acuminate,  oblique  at  the  base,  rough  and  dull  on  t In- 
upper  surface  and  softer  beneath,  dentate:  fruit  '-..-l  in.  long,  black-red, 
sweet.  Wood  yellow.  Most  abundant  South,  but  growing  as  far  north  as 
Massachusetts. 


348  THE     KINDS     OF    PLANTS 

M.  alba,  Linn.  White  mulberry.  Fig.  511.  Leaves  light  green  and 
usually  glossy  above,  the  veins  prominent  and  whitish  beneath,  the  teeth 
usually  rounded  or  obtuse:  fruit  of  variable  size,  often  \y2  in.  long,  whitish, 
violet,  or  purple.  China;  planted  for  ornament  and  for  its  fruit,  also  for 
feeding  silkworms.    The  much-planted  Russian  mulberry  is  a  form  of  it. 

5.  CANNABIS.    Hemp. 

Tall,  strong,  dioecious  herbs  with  5-7  leaflets:  fertile  flowers  in  clus- 
ters, with  1  sepal  surrounding  the  ovary,  and  2  long,  hairy  stigmas:  sterile 
flowers  in  racemes  or  panicles,  with  5  sepals  and  5  drooping  stamens. 

C.  sativa,  Linn.  Hemp.  Six  to  10  ft.,  strong-smelling,  blooming  all 
summer:  leaflets  lanceolate,  large  toothed.  Old  World;  cultivated  for  fiber 
and  sometimes  escaped  in  waste  places. 

6.  HUMULUS.    Hop. 

Twining  dioecious  herbs  of  tall  growth,  with  5  sepals  in  the  sterile 
flowers,  the  stamens  erect:  fertile  flowers  with  1  sepal, 
2  flowers  under  each  scale  of  a  short,  thin  catkin  which 
becomes  a  kind  of  cone  or  "hop." 

H.  Lupulus,  Linn.  Common  hop.  Perennial,  rough- 
hairy:  leaves  broad-ovate,  deeply  3-lobed  (only  rarely 
5-7-lobed):  sterile  flowers  in  panicles  2-6  in.  long:  pis- 
tillate catkin  enlarging  into  a  "hop"  often  2  in.  or 
more  long.  A  native  plant,  cultivated  for  hops  and 
sometimes  for  ornament. 
s$  H.    japonicus,    Sieb.  &  Zucc.    Japanese  hop.     Fig. 

511.    Moms  alba.       179.     Annual:    leaves   not    less   than    5-lobed:    fertile 
catkin    not    enlarging    into    a    hop.      Japan;    much 
cultivated   for   ornament. 

7.  URTICA.    Nettle. 

Erect  herbs  with  opposite  simple  leaves  and  stinging  hairs,  and  monoe- 
cious or  dioecious  flowers  in  racemes  or  dense  clusters,  the  calyx  of  4 
separate  sepals:  stamens  4:  stigma  sessile:  fruit  an  ovate  flat  achene.  The 
following  are  perennials  with  flowers  in  panicled  spikes: 

U.  gracilis,  Ait.  Common  nettle.  Two  to  6  ft.:  leaves  ovate-lanceolate, 
serrate,  on  long  petioles.    Common  in  low  grounds. 

U.  dioica,  Linn.  Not  so  tall:  leaves  ovate-cordate  and  deeply  serrate,  on 
rather  short  petioles,  downy  underneath.    Weed  from  Europe,  very  stinging. 


XI.  ARISTOLOCHIACE^. 

Birthwort  Family.   Dutchman's  Pipe  Family. 

Low  acaulescent  herbs,  or  tall  twining  vines:  leaves  basal  or  alter- 
nate, without  stipules,  petiolate,  roundish  or  kidney-shaped:  flowers 
regular  or  irregular,  perfect:  perianth-tube  brown  or  dull,  valvate  in 


ARISTOLOCHIA — POLYGONUM  349 

bud,  adherent  to  ovary:  stamens  6-12,  epigynous,  and  adherent  to 
base  of  the  styles:  ovary  6-celled,  pistil  1.  A  small  family  of  about  200 
species,  sparingly  represented  in  this  country.  Many  of  the  members 
have  aromatic  or  bitter-tonic  properties. 

a.  Low  stemless  herbs 1.  Asarum 

aa.  Leafy-stemmed  herbs,  or  woody  climbers 2.  Aristolochia 

1.  ASARUM.    Wild  Ginger. 

Perennial  spreading  herbs:  loaves  large,  kidney-shaped,  pubescent: 
flower  brown,  inconspicuous,  borne  on  a  short  peduncle  arising  from  between 
the  petioles:  rootstocks  creeping,  elongated,  very  aromatic. 

A.  canadense,  Linn.  Leaves  in  pairs,  large,  reniform,  but  more  or  less 
pointed  at  tip,  soft-hairy  with  a  silky  finish:  flower  greenish  outside,  purple- 
brown  within,  consisting  of  a  3-lobed  calyx,  adnate  to  ovary:  stamens  12, 
the  filaments  longer  than  the  anthers.    Common  in  rich  woods.    April,  May. 

2.  ARISTOLOCHIA.    Dutchman's  Pipe. 

Herbs  or  tall  vines,  with  alternate,  petiolate  leaves,  cordate,  entire 
and  palmately  nerved:  flowers  irregular,  the  calyx  tubular,  the  tube  oddly 
inflated  above  ovary  and  contracted  at  throat,  shaped  like  a  much-bent 
pipe,  the  margin  reflexed  or  spreading,  3-6-lobed  or  appendaged:  sta- 
mens 6. 

A.  macrophylla,  Lam.  (A.  Sipho,  L'Her.).  Calyx-tube  about  1-1^2  in. 
long,  curved  to  resemble  a  Dutch  pipe,  the  margin  spreading,  brownish- 
purple:  leaves  large,  smooth,  dark  green,  round  kidney-shaped.  Wild  in 
rich  woods;  May;  often  cultivated. 


XII.  POLYGONACE.E.   Buckwheat  Family. 

Herbs,  mostly  with  enlarged  joints  or  nodes  and  sheaths  (repre- 
senting stipules)  above  them:  leaves  simple  and  usually  entire,  alter- 
nate: flowers  small,  apetalous,  usually  perfect  and  generally  borne  in 
spikes  or  dense  clusters:  stamens  4-12,  attached  to  the  very  base 
of  the  3-5-merous  calyx:  ovary  1-loculed,  ripening  into  a  3-4-angled 
achene.  Thirty  or  more  genera  and  about  600  widely  dispersed  species. 
Characteristic  plants  are  buckwheat,  rhubarb,  dock,  sorrel,  smart- 
weed. 

a.  Root-leaves  1  ft.  or  more  across,  rounded I.  Rheum 

aa.  Root-leaves  narrow  or  not  prominent. 

b.   Calyx  of  6  sepals,  often  of  two  kinds 2.  Rumex 

bb.  Calyx  of  5  (rarely  4)  sepals,  all  alike. 

c.  Flowers  white  and  fragrant 3.  Fagopyrum 

cc.  Flowers  greenish  or  pinkish,  not  distinctly  fragrant.  .4.  Polygonum 


350 


THE    KINDS    OF    PLANTS 


1.  RHEUM.    Rhubarb. 

Very  large-leaved  perennials,  sending  up  stout  hollow  flower-stalks  in 
early  summer  which  bear  smaller  leaves  with  sheathing  bases:  sepals  6,  all 
alike,  withering  rather  than  falling,  and  persisting  beneath  the  3-winged 
achenes:  stamens  9:  styles  3.    Old  World. 

R.    Rhaponticum,    Linn.      Rhubarb.     Pie- 
plant.    Figs.   81,   82.     Leaves    1    ft.   or  more 
across,  the  thick  petioles  edible:  fls.  white,  in 
elevated  panicles. 

RUMEX.   Dock.   Sorrel. 

Perennial  often  deep-rooted  plants  with  herbage 
bitter  or  sour:  sepals  6,  the  3  outer  large  and  spread- 
ing, the  3  inner  (known  as  "valves")  enlarging  after 
flowering  and  one  or  more  of  them  often  bearing  a 
grain-like  tubercle  on  the  back;  stamens  6,  styles  3; 
flowers  in  panicles  or  interrupted  spikes. 


512.   Rumex  Acetosella. 


Docks:   herbage  bitter:  valves  often  grain-bearing:  flowers  mostly  perfect: 
leaves  not  arrow-shaped. 


R.  obtusifolius.  Linn.  Bitter  dock.  Lower  leaves  oblong-cordate  and 
obtuse,  not  wavy:  one  valve  usually  grain-bearing.    Weed  from  Europe. 

R.  crispus,  Linn.  Curly  dock.  Leaves  lanceolate,  wavy  or  curled:  all 
valves  usually  grain-bearing.    Weed  from  Europe. 

aa.    Sorrels:  herbage  sour:    valves  not  grain-bearing: 
flowers  diwcious:  leaves  arrow-shaped. 

R.  Acetosella,  Linn.  Common  ^or  sheep  sorrel. 
Fig.  512.  Low  (1  ft.  or  less):  lvs.  mostly  arrow- 
shaped  at  base:  flowers  brownish,  small,  in  a  ter- 
minal panicle.    Common  in  sterile  fields.    Europe. 

3.  FAGOPYRUM.   Buckwheat. 

Fast-growing  annuals,  with  somewhat  triangular 
leaves,  and  fragrant  flowers  in  flattish,  panicle-like 
clusters:  calyx  of  5  parts:  stamens  8:  fruit  a  trian- 
gular achene.    Old  World. 

F.  esculentum,  Moench.  Common  buckwheat. 
Fig.    513.      Leaves   triangular-arrow-shaped,    long- 

petioled:  flowers  white,  in  a  compound  cluster:  achene  with  regular  angles. 
Flour  is  made  from  the  grain. 

F.  tataricum,  Gaertn.  India  wheat.  Slenderer,  the  leaves  smaller  and 
more  arrow-shaped  and  short-petioled:  flowers  greenish  or  yellowish,  in 
simple  racemes:  achene  notched  on  the  angles.    Somewhat  cultivated. 


513. 
Fagopyrum  esculentum. 


KNOTWEED    FAMILY 


351 


4.  POLYGONUM.    Knotweed.    Smahtweed. 

Low  weedy  plants,  or  some  exotic  ones  tall  and  cultivated,  blooming  in 
summer  and  fall,  the  small  pinkish  or  greenish  flowers  mostly  in  racemes  or 
spikes  (in  the  Knotweeds  in  the  leaf-axils):  calyx  usually  5-parted:  stamens 
4-9:  stigmas  2  or  3:  black  achene  lenticular  or  triangular. 

a.  Knotweeds:  /lowers  sessile  in  the  axils  of  the  leaves,  greenish  and  very  small. 

P.  aviculare,  Linn.  Common  knotweed.  Doorweed.  Fig.  210.  Pros- 
trate or  creeping,  bluish  green  wiry  plant,  growing  along  the  hard  edges  of 
walks  and  in  yards,  and  commonly  mistaken  for  sod:  leaves  small,  mostly 
oblong,  entire:  sepals  very  small,  green  with  a  broad  white  margin:  stamens 
5  or  more:  stigmas  usually  3.    Annual. 

P.  erectum,  Linn.  Taller  knotweed.  One  ft.  or  more  high:  leaves  three 
or  four  times  larger,  oblong  or  oval  and  obtuse.    Common  annual. 

aa.  Smarhveeds:  flowers  in  terminal  spikes,  mostly  pinkish. 

b.  Sheaths  of  leaves   (surrounding  stem)  hairy  on  the  edge,  or 

the  margin  with  a  spreading  border. 

P.  orientate,  Linn.  Prince's  feather.  Several  feet  tall,  soft- 
hairy:  flowers  in  long  cylindrical  nodding  spikes:  leaves  ovate: 
stamens  7.     India;  cultivated.    Annual. 

P.  Persicaria,  Linn.  Smartweed.  Lady's  thumb  (from  the 
dark  blotch  near  the  center  of  the  leaf).  Fig.  514.  About  1 
ft.:  leaves  lanceolate:  spikes  oblong,  dense  and  erect:  stamens 
usually  6:  stigmas  2.    Weed  from  Europe. 

P.  Hydropiper,  Linn.  Smartweed.  Herbage  very  pungent 
or  "smarty:"  leaves  oblong-lanceolate:  spikes  short  and 
nodding,  the  flowers  greenish:  stamens  6:  stigmas  3.  Low 
grounds.    Annual. 

P.  hydropiperoides,  Michx.  Smartweed.  Herbage  not 
pungent:  spikes  slender  and  erect,  the  flowers  whitish:  sta- 
mens 8:  stigmas  3.    In  very  wet  places.    Perennial. 

P.    acre,   HBK.    Smartweed.      Herbage    pungent:    leaves 
linear  or  lanceolate,  long-pointed:  spikes  slender  and  erect:  flowers  white  or 
blush:  stamens  8:  stigmas  3.    Low  grounds.    Perennial. 

bb.  Sheaths  of  leaves  not  hairy,  nor  the  margin  bordered. 
P.  pennsylvanicum,  Linn.    Smartweed.   Pungent:  plant  with  conspicuous 
glandular  hairs  above:  leaves  lanceolate:  spikes  short-oblong  and  erect,  the 
flowers  purplish:  stamens  8:  stigmas  2.    Low  ground.    Annual. 


XIII.  EUPHORBIACE.E.   Spurge  Family. 

Trees,  shrubs  or  herbs,  often  with  milky,  pungent  juice,  some- 
times poisonous:  flowers  monoecious  or  dioecious,  mostly  apetalous, 
usually  small  and  inconspicuous.    The  family  is  large,  in  wanner  parts 


352  THE     KINDS    OF    PLANTS 

of  the  world.  The  determination  of  the  genera  and  species  is  difficult. 
Euphorbia  and  Ricinus  will  sufficiently  explain  the  flower  structure  for 
the  beginner. 

A.  Flowers  in  a  cup-like  involucre,  which  imitates  a  perianth: 

flowers  dioecious,  without  calyx  or  corolla 1.  Euphorbia 

AA.  Flowers,  not   in  an  involucre,  but  in  a  terminal    panicle: 

flowers  dioecious,  calyx  present,  but  no  corolla 2.  Ricinus 

1.  EUPHORBIA.    Spurge. 

Flowers  monoecious  inclosed  in  an  involucre,  which  is  4-5-lobed  and 
often  showy,  resembling  a  perianth:  staminate  flowers  each  consisting  of 
a  stamen  jointed  to  filament-like  pedicel,  subtended  by  a  minute  bract, 
attached  on  the  inner  surface  of  the  involucre:  the  solitary  pistillate  flower, 
standing  at  the  bottom  of  the  involucre,  is  at  length  protruded  on  a  stalk: 
capsule  3-lobed  and  3-celled:  styles  3,  each  2-cleft:  stigmas  6.  Many  of  the 
species  are  cultivated  for  ornamental  purposes,  as  E.  splendens,  Crown  of 
Thorns;  E.  Cyparissias,  Cypress  spurge,  common  in  old  yards  and  about 
cemeteries,  where  it  has  run  wild. 

E.  corollata,  Linn.  Flowering  spurge.  Perennial,  2-3  ft.,  slender- 
branched:  leaves  mostly  alternate,  or  the  uppermost  ones,  or  those  on 
the  branches  opposite,  whorled,  oval,  rather  thick,  usually  pale  beneath: 
flowering  branches  much  forked:  involucres  terminal,  or  on  peduncles,  from 
the  forks  of  the  branches,  the  lobes  snowy  white,  appearing  like  petals  with 
oblong  yellowish  green  glands  at  base  of  each.  In  dry  or  sandy  soil,  common. 
July  to  October. 

E.  maculata,  Linn.  Small  plant,  prostrate  or  spreading,  the  branches 
slender  and  radiating,  dark  green,  often  dark  red:  leaves  oblong-linear, 
usually  with  red-brown  spots  in  center:  involucre  minute,  the  corolla-like 
appendages  narrow,  white  or  red.  A  common  inconspicuous  weed  through- 
out North  America,  except  the  extreme  north. 

E.  pulcherrima,  Willd.  Poinsettia.  Floral  leaves  brilliant  red  and 
appearing  like  flaming  blossoms:  flowers  in  a  greenish  involucre,  with  a 
large  yellow  gland  on  summit.  A  Mexican  species,  well  known  as  an 
ornamental  greenhouse  plant. 

2.  RICINUS.    Castor-oil  Plant.    Figs.  313-316. 

Tall  stately,  perennial  herb  (annual  North),  with  large,  alternate,  pal- 
mately  cleft  leaves:  flowers  monoecious,  apetalous,  greenish,  in  terminal 
racemes  or  panicled  clusters,  the  pistillate  flowers  above  the  others;  styles 
large,  reddish. 

R.  communis,  Linn.  Castor  bean.  Palma  Christi.  Stem  erect  from 
3-12  ft.,  somewhat  branched:  leaves  very  large,  peltate,  lobes  acute,  pointed, 
toothed:  seeds  smooth,  black,  mottled  or  variegated  with  gray  and  brown. 
Grown  for  medicinal  and  ornamental  purposes.  Tropical.  There  are  many 
forms  in  cultivation. 


pinks  353 


XIV.  CARYOPHYLLACE.E.   Pink  Family. 

Herbs,  with  opposite,  mostly  narrow,  entire  leaves  without  conspic- 
uous veins:  flowers  4-5-merous,  sometimes  apetalous,  with  stamens 
twice  or  less  the  Dumber  of  sepals  or  petals,  and  2-5  styles  which 
may  be  wholly  separate  or  partially  united:  pod  usually  a  1-loculed 
capsule  commonly  inclosed  in  the  calyx,  mostly  splitting  from  the 
top,  th<>  seeds  usually  attached  to  a  central  column.  Genera  between 
30  and  40,  species  about  1,000.  Representative  plants  are  pink,  car- 
nation, bouncing  Bet,  catchfly,  chickweed,  corn-cockle,  lychnis,  spurry. 

a.  Flowers  polypetalous,  with  sepals  united  into  a  tube. 

B.  Bracts  at  the  base  of  the  calyx 1.  Dianthus 

bb.  No  bracts  at  base  of  calyx. 

c.  Styles  2 2.  Saponaria 

cc.  Styles  4-5 3.  Lychnis 

ccc.   Styles  3 4.  Silene 

aa.   Flowers  often  apetalous,  the  sepals  nearly  or  quite  distinct. 

b.  Styles  3  or  4 5.  Stellaria 

bb.  Styles  5 6.  Cerastium 

1.  DIANTHUS.    Pink. 

Showy-flowered  small  herbs,  with  striate,  many-furrowed 
calyx  and  sepal-like  bracts  at  its  base:  petals  with  slender 
claws  or  bases,  the  limb  usually  toothed  or  fringed:  styles  2.  *  IT^^6 

a.  Flowers  single  on  ends  of  branches. 

D.    chinensis,    Linn.      China    or   florists'    pink.     Leaves 
short-lanceolate,  not  grass-like:  calyx-bracts  linear-acute  and 
as  long  as  the  calyx:  petals  in  white  and  shades  of  red,  very 
showy.    China.    Perennial,  but  grown  as  an  annual   (mostly   f^]/ 
under  the  florists'  name  D.  Hcddcwigi). 

D.  plumarius,  Linn.    Grass  or  Scotch  pink.    Common  pink   515'    Dianthus 
of  old  gardens,  from  Europe.     Low,  growing  in   mats,  glau- 
cous-blue:    leaves  grass-like:   flowers  very  fragrant,  deep-fringed,  white  or 
pink.     Perennial. 

D.  Caryophyllus,  Linn.  Carnation.  Two  ft.  or  more,  with  wiry  stems, 
glaucous-blue:  leaves  grass-like:  calyx-bracts  short  and  broad:  petals  more 
or  less  toothed  but  not  fringed:  flowers  fragrant.    Europe. 

aa.  Flowers  in  compact  clusters. 

D.  barbatus,  Linn.  Sweet  William.  Fig.  515.  One  ft.  or  more,  erect, 
green:  flowers  small,  in  dense  clusters  in  red  and  white.  Old  World;  common 
in  old  gardens. 

W 


<T 


354  THE     KINDS    OF    PLANTS 

2.  SAPONARIA.    Soapwort. 

Calyx  cylindrical  or  angled,  5-toothed,  with  no  bracts  at  its  base: 
stamens  10:  styles  2:  pod  4-toothed  at  top  (Fig.  282). 

S.  officinalis,  Linn.  Bouncing  Bet.  Perennial,  forming  colonies  in  old 
yards  and  along  roads,  1-2  ft.  high,  glabrous,  with  ovate  or  oval  leaves: 
flowers  1  in.  across,  white  or  rose,  in  dense  clusters,  often  double,  the  petals 
with  a  crown.    Europe.    Common. 

3.  LYCHNIS.    Lychnis.    Cockle. 

Annual  or  perennial,  with  styles  usually  5,  and  pod  opening  by  5  or  more 
teeth:  calyx  5-toothed  and  10-  or  more-nerved,  naked  at  the  base:  stamens  10. 

L.  Githago,  Scop,  (or  Agrostemma  Githago,  Linn.).  Fig.  181.  Corn 
cockle,  because  it  is  a  common  weed  in  wheat  fields  (wheat  is  known  as 
corn  in  Europe),  its  seeds  not  being  readily  separated  from  wheat  because 
of  their  similar  size  and  its  seasons  corresponding  with  those  of  wheat:  annual, 
2-3  ft.,  hairy:  flowers  purple-red  and  showy,  on  very  long  stalks,  the 
petals  crowned  and  the  calyx-lobes  long  and  leafy:  leaves  very  narrow. 
Europe. 

L.  Coronaria,  Desv.  Dusty  Miller.  Mullein  pink.  Biennial  or  per- 
ennial, white-woolly  all  over:  leaves  oblong:  flowers  rose-crimson,  showy. 
Europe.    Old  gardens  and  along  roads. 

4.  SILENE.   Campion.   Catchfly. 

Annual  or  perennial  herbs,  with  white,  pink,  or  red  flowers,  solitary  or 
in  cymes:  calyx  often  inflated,  5-toothed,  10-  to  many-nerved,  with  no 
bracts  at  base;  petals  5,  clawed,  sometimes  with  crown  or  scale  at  base  of 
blade;  stamens  10;  styles  3  (rarely  4  or  5);  ovary  1-celled  (or  incompletely 
2-4-celled):  fruit  a  capsule,  or  pod,  1-celled  or  3-celled  at  base,  dehiscent  by 
3  or  6  teeth  at  apex,  many-seeded.  A  viscid  secretion  covers  the  calyx  and 
stems  of  certain  species,  by  which  creeping  insects  are  caught,  whence  the 
name  "catchfly." 

S.  stellata,  Ait.  Starry  campion.  Perennial,  2-3  ft.  high:  leaves  ovate- 
lanceolate,  acuminate,  in  whorls  of  4  (at  least  the  upper  ones) :  flowers  in 
panicled  cymes;  calyx  bell-shaped,  loose  and  inflated;  petals  fringed, 
crownless,  white.    July.    Open  woods. 

S.  latifolia,  Britten  &  Rendle.  Bladder  campion.  Perennial,  1-2  ft.: 
leaves  ovate-lanceolate,  acute,  opposite:  flowers  in  panicles,  inclined  or 
drooping:  calyx  globular,  thin  and  much  inflated,  conspicuously  veined; 
petals  2-cleft,  white.  Roadsides,  fields  and  waste  places.  Common  eastward. 
Naturalized  from  Europe. 

S.  pennsylvanica  Michx.  Wild  pink.  Perennial,  viscid-pubescent  above, 
4-10  in.:  basal  leaves  spatulate  or  cuneate,  narrowed  into  petioles;  stem- 
leaves  lanceolate,  sessile,  opposite:  flowers  in  terminal,  few-flowered  cymes; 
calyx  narrow;  petals  wedge-shaped,  slightly  emarginate  (or  eroded)  on 
edge,  pink-red,  crowned.    In  dry  soil  in  eastern  states. 

S.  virginica,  Linn.  Fire  pink.  Perennial,  1-8  ft.:  lower  leaves  thin, 
spatulate,  the  cauline  oblong  or  lanceolate,  sessile:  flowers  few  in  a  loose 


516.   Stellaria  media. 


PINK   FAMILY  355 

cyme,  peduncled,  showy,  1^-2  in.  broad;  calyx  bell-like,  enlarged  as  pod 
matures:  petals  2-cleft,  crowned,  bright  crimson:  stem  viscid-pubescent. 
Open,  dry  woods.    May  to  September. 

S.  noctifldra,  Linn.  Night-flowering  catchfly.  Annual:  lower  leaves 
spatulate  or  obovate,  the  upper  linear:  flowers  large,  few,  pedicelled, 
in  loose  panicle,  opening  at  dusk  for  the  night:  very  fragrant:  calyx-tube 
elongated,  noticeably  veined,  with  awl-like  teeth:  petals  2-cleft;  white, 
crowned.  Weed  introduced  from  Europe.  July  to 
September. 

5.  STELLARIA.    Chickweed. 

Small,  weak  herbs  with  sepals  4-5,  petals  of  equal 
number  and  deeply  cleft  or  sometimes  wanting;  stamens 
10  or  less;  styles  usually  3:  pod  opening  by  twice  as 
many  valves  as  there  are  styles. 

S.    media,    Cyrill.      Common   chickweed.    Fig.  457.    & 
Little  prostrate  annual,  making  a   mat    in    cultivated     ,_£ 
grounds,  with  ovate  or  oblong  leaves  mostly  on  hairy 
petioles:    flowers  solitary,  minute,   white,  the  2-parted 
petals  shorter  than  the  calyx,  the  peduncle  elongating  in  fruit.    Europe; 
very  common.    Blooms  in  cold  weather. 

6.  CERASTIUM.    Mouse-ear  Chickweed. 

Differs  from  Stellaria  chiefly  in  having  5  styles  and  pod  splitting  into 
twice  as  many  valves.  The  two  following  gray  herbs  grow  in  lawns.  From 
Europe. 

C.  viscosum,  Linn.  Annual,  about  6  in.  high:  leaves  ovate  to  spatulate: 
flowers  small,  in  close  clusters,  the  petals  shorter  than  the  calyx,  and  the 
pedicels  not  longer  than  the  acute  sepals. 

C.  vulgatum,  Linn.  Perennial  and  larger,  clammy-hairy:  leaves  oblong: 
pedicels  longer  than  the  obtuse  sepals,  the  flowers  larger. 


XV.  RANUNCULACE.E.   Crowfoot  or  Buttercup  Family. 

Mostly  herbs,  with  various  habits  and  foliage:  parts  of  the  flower 
typically  all  present,  free  and  distinct,  but  there  are  some  apetalous 
and  dioecious  species:  stamens  many;  pistils  many  or  few,  in  the 
former  case  becoming  achenes  and  in  the  latter  usually  becoming  folli- 
cles. Upwards  of  30  genera  and  1,000-1,200  species.  Characteristic 
plants  are  buttercup,  anemone,  meadow-rue,  marsh-marigold  or 
cowslip,  adonis,  clematis,  larkspur,  aconite,  columbine,  baneberry, 
peony.    Known  from  Rosacese  by  the  hypogynous  flowers. 

a.  Plants  not  climbing:  herbs. 

B.   Fruits  achenes,  several  or  many  from  each  flower. 


356  THE    KINDS    OF    PLANTS 

c.  True  petals  none,  but  the  sepals  petal-like    (and 
involucre  often  simulating  a  calyx). 
d.  Flowers  in  small  umbels,  or  peduncles  1-fld. 
e.  Involucre    of   2    or   more   lvs.    some    distance 

below  the  flower 1.  Anemone 

ee.  Involucre  of  3  sepal-like  leaves  close  to  the  flower  2.  Hepatica 
eee.  Involucre  of  3  compound  lvs.,  sessile  at  base 

of  umbel:  pistils  fewer  than  in  Anemone 3.  Anemonella 

dd.   Flowers  in  panicles  or  corymbs 4.  Thalictrum 

cc.  True  petals  present :  yellow 5.  Ranunculus 

bb.  Fruits,  follicles. 
c.  Flowers  regular. 

d.  Petals  each  spurred 6.  Aquilegia 

dd.  Petals  none:  sepals  petal-like,  yellow 7.  Caltha 

ddd.  Petals  many:  fls.  very  large  and  of  shades  of  red: 

plant  bushy 8.  Pseonia 

cc.  Flowers   irregular;   upper   sepal   spurred;   2   petals 

spurred 9.  Delphinium 

bbb.  Fruits,  berries,  red  or  white. 

c.  Flowers  with  petals  and  3-5  petal-like  sepals:  fls. 

small,  white,  in  a  short  raceme 10.  Actsea 

aa.  Plants  climbing  by  the  leaf-stalks:  stem  woody 11.  Clematis 

1.  ANEMONE.    Anemony.    Windflower. 

Low  perennial  herbs  with  mostly  showy  apetalous  flowers  and  an  invo- 
lucre of  2  or  more  mostly  divided  leaves  standing  some  distance  below  the 
flower:  pistils  ripening  into  a  head  of  achenes. 

a.   Achenes  woolly  or  silky. 

A.  japonica,  Sieb.  &  Zucc.  Japanese  anemony.  Three  ft.,  blooming  in 
fall,  with  pink  or  white  flowers  2-3  in.  across:  leaves  with  3  cordate-ovate 
notched  leaflets.    Much  planted. 

A.  virginiana,  Linn.  Two  ft.,  with  involucre  of  three  3-parted  leaves: 
flowers  on  long  stalks  arising  in  succession  from  succeeding  nodes:  sepals  5, 
acute,  greenish  white:  head  of  fruit  oblong,  J^  in.  long.    Woods. 

aa.   Achenes  not  woolly  or  silky. 
A.  quinquefolia,  Linn.   (A.  nemorosa  of   some).      Common   windflower. 
Low,  about  6  in.,  blooming  in  rich  woods  in  early  spring:  involucral  leaves  3, 
each  with  3  or  5  long  leaflets:  flowers  white,  purplish  outside,  pretty. 

2.  HEPATICA.   Liverleaf.    Mayflower  of  some  places. 

Differs  from  Anemone  chiefly  in  having  3  simple  sepal-like  bracts  be- 
neath the  flower  (but  they  are  sometimes  a  half-inch  removed  from  it): 
flowers  in  earliest  spring,  white,  blush,  or  blue,  on  simple  hairy  scapes: 
leaves  broad,  3-lobed.    Woods. 

H.  triloba,  Chaix.    Leaves  with  rounded  lobes. 

H.  acutiloba,  DC.   Leaves  with  acute  lobes. 


CROWFOOT    FAMILY  357 

3.  ANEMONELLA.    Rue  Anemone. 

Attractive  slender  perennial  herb,  resembling  Anemone:  basal  Leaves 
2  or  3  times  compound:  involucre  of  3  compound  leaves  at  base  of  the 
umbel:  leaflets  petioled:  flowers  in  a  terminal  umbel,  on  slender  pedicels; 
petals  wanting;  sepals  5-10;  white  or  pinkish,  1  in.  broad,  petal-like:  pistils 
4-15;  stigma  broad,  sessile  on  carpels,  glabrous  and  deeply  grooved. 

A.  thalictroides,  Spach.  Rue  anemone.  Stem  slender,  6-10  in.,  appear- 
ing in  earliest  spring  before  the  2-3  ternately  compound  basal  leaves,  rising 
from  a  cluster  of  tuberous  roots:  sepals  5-10,  bright,  quite  lasting.  A  com- 
mon spring  flower  of  the  woodland,  appearing  with  the  Wood  Anemone  or 
Windflower  and  easily  confused  with  it. 

4.  THALICTRUM.    Meadow  Rue. 

Mostly  smooth  perennial  herbs,  erect,  sometimes  several  feet  high  : 
panicled  flowers  small,  greenish  and  inconspicuous,  often  dioecious,  or 
polygamous:  foliage  light,  graceful,  the  alternate  leaves  being  2-4  ternately 
compound,  with  the  leaflets  and  divisions  stalked:  calyx  of  4-5  petal-like 
greenish  sepals,  soon  falling;  stamens  many;  ovaries  4-15,  1-seeded. 

T.  dioicum,  Linn.  Early  meadow  rue.  Flowers  dicecious,  green  or  pur- 
plish, in  loose  panicles:  leaflets  thin  and  delicate,  3-7-lobed,  pale  beneath, 
somewhat  drooping  on  the  petiolules:  anthers  yellow,  drooping  on  thread- 
like filaments:  achenes  about  8,  sessile  or  nearly  so:  1-2  ft.  high.  Common 
in  woodlands.    April  and  May. 

T.  polygamum,  Muhl.  Tall-meadow  rue.  Coarser,  ranker  and  later  than 
T.  dioicum,  4-8  ft.  high:  filaments  of  stamens  broad,  spatulate:  achenes 
stalked:  flowers  polygamous,  sepals  white. 

T.  dasycarpum,  Fisch.  &  Lall.  Purplish  meadow  rue.  Stem  2-5  ft.  high, 
usually  purplish:  stem-leaves  almost  sessile:  leaflets  thick,  dark  green  above, 
pale  and  waxy  or  downy  beneath,  margins  slightly  rolled  or  thickened: 
flowers  polygamous  or  dicecious,  greenish  and  purplish:  anthers  drooping 
on  filiform  filaments.    June  to  August. 

5.  RANUNCULUS.   Crowfoot.   Buttercup.   Figs.  202,  203,  207,  268. 

Perennials  or  annuals,  with  mostly  yellow  flowers;  sepals  5;  petals  5 
and  bearing  a  little  pit  or  scale  at  the  base  inside:  leaves  alternate:  achenes 
many  in  a  head. 

R.  acris,  Linn.  Tall  buttercup.  Two  to  3  ft.,  from  a  fibrous  root:  Leaves 
3-parted,  all  the  divisions  sessile  and  again  3-cleft:  flowers  bright  yellow. 
Europe,  but  now  a  common  weed.    Summer. 

R.  bulbosus,  Linn.  Earlier  and  only  half  as  tall,  from  a  bulbous  base: 
leaves  3-parted,  the  lateral  divisions  sessile  and  the  terminal  one  Btalked: 
peduncles  furrowed:  flowers  bright  yellow.    Europe;  common  eastward. 

R.  septentrionalis,  Poir.  Stems  more  or  less  prostrate  at  base,  often 
forming  long  runners:  leaves  3-divided,  divisions  all  stalked  and  3-lobed  or 
-parted:  petals  obovate,  yellow.    Wet  places. 

R.  abortivus,  Linn.  Glabrous,  biennial  herb;  6  in.  to  2  ft.,  branching: 
basal   leaves  heart-shaped  or  kidney-form,  crenate   (sometimes  lobed),  on 


358  THE    KINDS    OF    PLANTS 

long  stalks:  later  leaves,  often  3-5-lobed  or  -parted,  and  sessile  or  nearly  so: 
petals  small,  yellow,  not  equal  to  the  sepals:  styles  very  short,  curved. 
Shady  woods  and  along  stream-sides.    April  to  June. 

R.  micranthus,  Nutt.  Pubescent,  smaller  than  preceding  and  basal 
leaves  ovate,  but  not  heart-shaped,  some  3-parted:  fairly  common. 

R.  recurvatus,  Poir.  Usually  pubescent,  erect,  branching,  1-2  ft. :  leaves 
all  petioled  and  similarly  3-parted :  sepals  longer  than  the  pale  yellow  petals 
and  recurved:  beaks  of  achenes  strongly  hooked.    Common.   Spring. 

6.  AQUILEGIA.    Columbine. 

Upright  herbs,  with  compound  leaves  which  have  petioles  expanded 
at  the  base:  sepals  5,  somewhat  petal-like;  petals  5,  each  one  produced 
into  a  long  nectary  spur ;  pistils  5 :  fruit  a  several-seeded  follicle.  Delphinium 
or  larkspur  is  an  allied  genus. 

a.  Spurs  straight. 

A.  canadensis,  Linn.  Common  wild  columbine.  Often 
incorrectly  called  honeysuckle.  Fig.  517.  About  2  ft.: 
leaflets  rounded  or  obovate,  toothed  at  top:  flowers 
about  2  in.  long,  drooping,  scarlet  and  orange  or  nearly 
yellow,  the  stamens  projecting.  Common  on  rocks. 
A.  chrysantha,  Gray.  Yellow  columbine.  Flowers 
517.     "  bright  yellow,  often  tinged,  erect  or  becoming  so.  New 

Aquilegia  canadensis.    Mexico  and  Arizona,  but  frequent  in  gardens. 

aa.  Spurs  hooked  at  the  end. 

A.  vulgaris,  Linn.  Blue  columbine.  A  European  species,  common  in 
gardens,  and  often  full  double:  flowers  varying  from  blue  and  purple  to 
white,  with  rather  short  and  thick  hooked  spurs. 

7.  CALTHA.    Marsh  Marigold.    Cowslip  (in  America) 

Low  tufted  herbs  with  undivided  leaves,  and  clusters  of  yellow  butter- 
cup-like flowers:  sepals  5-9,  petal-like;  petals  none;  pistils  5-10,  ripening 
into  several-seeded  follicles. 

C.  paliistris,  Linn.  About  1  ft.  high:  leaves  rounded  or  kidney-shaped, 
crenate  or  nearly  entire.    Wet  places,  in  early  spring.    Used  for  "greens." 

8.  P^ONIA.   Peony.    Piney. 

Stems  shrubby  and  perennial  or,  as  in  the  commoner  garden  forms,  her- 
baceous, from  thick,  fleshy  roots:  leaves  ternately  and  pinnately  compound: 
flowers  large,  terminal,  solitary;  sepals  5,  unequal,  leafy,  persistent;  petajs 
5  to  indefinite  in  number;  ovaries  3-5,  surrounded  by  a  disk:  fruit,  many- 
seeded  follicles.    Oriental. 

P.  officinalis,  Linn.  Common  garden  peony.  Large  flowers,  double, 
red,  pink,  flesh-colored  to  white;  carpels  2,  pubescent,  forming  2  erect, 
many-seeded  follicles.    June. 


CROWFOOT    FAMILY  359 

9.  DELPHINIUM.    Larkspur.    Figs.  224,  225,  269,  270. 

Stems  erect,  simple  or  branching,  with  alternate  leaves,  petioled,  pal- 
mat.  1\  -divided  or  -lobed:  flowers  in  a  terminal  raceme  or  panicle,  white,  blue, 
purple  and  showy,  with  irregular  sepals  and  petals;  sepals  5,  colored,  the 
upper  spurred  behind;  petals  4  (rarely  2),  the  upper  pair  spurred,  and  in- 
closed in  the  spur  of  the  sepal;  carpels  1-5,  sessile,  forming  many-seeded 
follicles.    Several  wild  and  cultivated  species. 

D.  Ajacis,  Linn.  Annual,  1-2  ft.:  flowers  purple,  roseate  or  white, 
sometimes  double,  many  in  crowded  racemes;  pistil  1:  follicle  pubescent, 
with  short,  stout  beak.  Cultivated  and  a  showy  garden  plant;  sometimes 
escaped  from  gardens. 

D.  tricorne,  Michx.  Perennial,  6  in.  to  1  or  2  ft.:  flowers  blue  or  white, 
in  few-flowered  racemes  (6-12):  leaves  5-parted,  the  divisions  3-5-cleft: 
pistils  3:  follicles  widely  diverging,  short-beaked.  In  rich  soil,  west  of 
Alleghanies.    April  to  June. 

10.  ACTJilA.    Baneberry. 

Erect,  perennial  plants,  in  rich  woods,  2-3  ft.,  with  conspicuous  red  or 
white  berries:  stems  mostly  simple,  bearing  large,  ternately  compound 
leaves,  the  leaflets  ovate  but  sharply  cut-lobed  or  toothed:  flowers  small, 
white,  in  thick  terminal  racemes;  sepals  3-5,  soon  falling;  petals  4-10,  long- 
clawed,  flat,  spatulate;  stamens  many,  filaments  white  and  slender;  ovary 
1,  with  a  broad,  sessile,  2-lobed  stigma,  many-ovuled. 

A.  alba,  Mill.  White  baneberry.  Raceme  oblong:  petals  truncate, 
pedicels  thickened,  and  usually  red:  berries  white,  ellipsoid.  Common  in 
woods.    April  to  June. 

A.  rubra,  Willd.  Red  baneberry.  Raceme  ovate  or  hemispherical; 
petals  acute;  pedicels  slender:  berries  cherry-red  (sometimes  white),  oval 
or  ellipsoid.  Common  in  woods,  especially  northward.  In  bloom,  April, 
May. 

11.  CLEMATIS.   Virgin's  Bower.   Figs.  77,  178. 

Herbs,  or  somewhat  woody,  generally  climbing  by  clasping  petioles: 
leaves  opposite,  simple  or  compound:  flowers  apetalous,  or  petals  very  small; 
sepals  4  (rarely  more)  and  colored;  stamens  many,  a  number  of  them  (some- 
times all)  usually  sterile;  pistils  many  in  a  head,  bearing  the  persistent, 
plumose  or  silky  styles.    Many  large-flowered  cultivated  forms. 

C.  verticillaris,  DC.  A  woody  climber,  nearly  smooth:  leaves  in  whorls 
of  4's,  each  3-foliate:  large,  purple  flowers  2-3  in.  across,  at  each  node. 
Not  common,  belonging  mainly  to  the  North  and  to  mountainous  districts. 
May,  June 

C.  Viorna,  Linn.  Leaves  mostly  pinnately  compound,  with  3-7  leaflets, 
entire,  or  3-lobed:  flowers  solitary  and  usually  nodding  on  long  peduncles, 
bell-shaped,  having  peculiarly  thick  sepals,  with  their  points  recurved; 
purplish-red  color:  the  long  akenes  plumose.   Climbing.   Pennsylvania,  west. 

May  to  August. 

C.    virginiana,    Linn.      Common    virgin's    bower.      Old-man    vine    (from 


360  THE    KINDS    OF    PLANTS 

the  heads  of  hairy  styles).  A  common  climbing  plant,  along  fences,  streams 
and  in  low  woodlands:  leaves  compound,  glabrous,  with  3  leaflets  cut  or 
lobed  and  nearly  heart-shaped  at  base:  flowers  small,  in  leafy  panicles,  poly- 
gamo-dicecious ;  petals  none,  but  sepals  whitish,  thin,  spreading:  styles 
long-plumed  in  fruit,  making  a  feathery  cluster.    July,  August. 


XVI.  BERBERIDACE^;.   Barberry  Family. 

Herbs  and  shrubs  with  alternate  or  radical  leaves,  sometimes  with 
stipules:  flowers  regular,  perfect  (except  1  genus),  hypogynous,  soli- 
tary or  racemed;  sepals  and  petals  usually  in  several  rows  of  3  each, 
and  calyx  colored;  stamens  as  many  as  petals  (rarely  more)  and  one 
opposite  to  each  petal:  anthers  opening  at  the  top  by  2  valves  or 
lids  (except  in  Podophyllum) :  pistil  1 :  fruit  a  berry  or  pod.  About  20 
genera  and  100  species. 

a.  Shrubs:  flowers  yellow:  berries  red  or  orange,  remaining 

on  branches  into  the  winter 1.  Berberis 

AA.  Herbs. 

b.  Flowers   on   leafless   scapes:   leaves   radical,    each  2- 

parted:  fruit  a  pod,  opening  at  the  top  by  a  lid 2.  Jeffersonia 

bb.  Flower    on    short    pedicel,    in    fork    between   2    large 

leaves:  fruit  a  large,  oval,  edible  berry 3.  Podophyllum 

1.  BERBERIS.    Barberry.    Figs.  168,  221. 

Shrubs,  often  spiny:  flowers  yellow,  in  drooping  racemes;  sepals  6-9, 
colored,  bracted;  petals  6,  each  with  2  basal  glandular  spots;  stamens  6, 
irritable,  bending  inward  when  touched;  pistil  1;  stigma  circular,  sessile: 
berries  sour,  1— few-seeded:  leaves  simple  or  compound,  bases  dilated  and 
jointed  on  short  petioles,  usually  spiny-toothed,  sometimes  reduced  to 
cleft  spines. 

B.  vulgaris,  Linn.  Common  barberry.  Leaves  with  repandly-toothed 
margins,  teeth  spinous-pointed  or  represented  by  branched  (3-pronged) 
spines:  berries  oblong,  scarlet,  acid.  Europe;  but  cultivated  and  naturalized 
in  eastern  and  middle  states. 

B.  canadensis,  Mill.  Shrub  1-3  ft.,  native  to  southern  mountains, 
with  oval  berries  and  few-flowered  racemes. 

B.  Thunbergii,  DC.  Cultivated,  low  shrub  with  small  entire  leaves  and 
handsome  horizontal  sprays:  flowers  solitary  or  in  pairs,  on  slender  pedicels, 
from  leaf -axils:  berries  bright  red,  remaining  on  the  twigs  into  the  winter: 
leaves  3^-1  in.  long,  also  red  in  fall.    Japan. 

2.  JEFFERSONIA.    Twin-leaf.    Rheumatism  Root. 

Perennial  glabrous  herb,  from  roots  of  matted,  blackish  fibers,  with 
ample  2-parted  leaves,  rising  on  long  petioles  from  the  roots:  scape  bearing  1 
terminal  large  white  flower;  sepals  4,  soon  falling;  petals  usually  8,  oblong; 


BERBERIDACE.E — NYMPHjEACEjE  361 

stamens  8,  with  linear  anthers  on  slim  filaments;  stigma  peltate,  with  many 
ovules  on  lateral  placentae:  pod  green,  leathery,  becoming  pear-shaped  and 
dehisces  by  a  lid,  opening  half-way  round  the  upper  part,  from  which  the 
many,  rounded  seeds,  arilled  on  one  side,  spill  forth. 

J.  diphylla,  Pers.  Scape  erect  to  8  or  12  in.:  leaves  divided  longitu- 
dinally into  2  parts,  with  usually  entire  margins.  Very  interesting  little 
plant  in  rich  woods,  spring:  sometimes  cultivated. 

3.  PODOPHYLLUM.    May  Apple.    Mandrake. 

Smooth  perennials  from  creeping  horizontal  rootstocks,  and  thick, 
fibrous  roots:  stems  smooth,  simple,  carrying  large,  peltate,  glossy-green 
leaves  and  a  solitary  white  flower:  sepals  6,  petal-like,  soon  falling;  petals 
6-9,  concave,  broad  and  large;  stamens  as  many  or  twice  as  many  as  petals; 
pistil  1,  with  sessile,  large,  thick,  stigma:  fruit  a  large,  fleshy,  oval,  1-celled 
berry,  filled  by  many  seeds,  each  seed  inclosed  in  a  pulpy  aril,  edible. 

P.  peltatum,  Linn.  Leaves  2,  large,  orbicular,  peltate,  deeply  5-9-lobed 
and  few-toothed:  flowers  fragrant,  solitary  from  the  common  axil  of  the  2 
stem  leaves,  borne  on  a  short,  recurved  peduncle:  petals,  large,  white,  wax- 
like: common  in  rich,  shady,  woodland,  often  in  large  patches.    May,  June. 


XVII.  NYMPrLEACE,E.   Water-Lilt  Familt. 

Aquatic,  perennial  herbs,  with  very  large  rootstocks  under  watei : 
leaves  large,  peltate  or  heart-shaped,  often  floating:  flowers  solitary, 
on  axillary  peduncles;  sepals  3-5  or  6;  petals  5  to  many;  stamens  5 
to  many,  with  large,  erect  anthers;  carpels  3  to  many,  distinct,  or  united 
in  a  circle  or  with  the  receptacle:  fruit  indehiscent,  or  group  of  distinct 
carpels.  Eight  genera,  of  wide  distribution  in  fresh  water.  The  great 
Victoria  Regia  of  the  Amazon,  and  often  cultivated,  belongs  here. 

a.  Flowers  white:  sepals  4 1.  Castalia 

aa.  Flowers  yellow:  sepals  5  or  more 2.  Nymphuu 

1.  CASTALIA.    Water-lily. 

Herbs  with  floating  leaves  and  beautiful,  large,  many-petaled  flowers: 
sepals  4,  white,  green  without;  petals  large,  wax-like,  gradually  becoming 
smaller,  and  passing  into  the  yellow  stamens  which  are  adherent  to  the 
many-celled  ovary;  stigmas  radiate  (as  in  a  poppy  head)  from  a  center: 
fruit  ripens  under  water. 

C.  odorata,  Woodville  &  Wood.  White  water-lily.  Flower  2  6  in.  across, 
very  sweet-scented:  petals  oftenest  white,  sometimes  tinged  with  pinkish. 
Common. 

2.  NYMPH&A.   Yellow  Pond-lily. 

Distinguished  from  the  water-lily  l>y  the  leaves,  which  are  more  or  less 
heart-shaped,  floating  or  erect:  also  by  the  flowers,  which  are  2-3  in.  in 


362  THE     KINDS    OF    PLANTS 

diameter,  with  small,  linear,  yellow  or  purplish  petals,  becoming  stamen-like 
toward  center:  fruit  ripens  above  water.  The  name  Nymphzea  is  sometimes 
applied  to  the  genus  Castalia. 

N.  advena,  Ait.  Spatterdock.  Leaves  oval,  thick,  6  in.  to  1  ft.  long, 
floating  or  erect:  flowers  yellow,  sepals  6  or  more,  not  equal;  petals  thick, 
truncate,  resembling  stamens. 

XVIII.  PAPAVERACE.E.   Poppy  Family. 

Herbs  with  milky  or  colored  juice  (acrid  and  narcotic),  alternate 
or  radical  exstipulate  leaves,  the  upper  rarely  opposite:  flowers  mostly 
single,  regular  or  irregular,  perfect;  sepals  2  (rarely  3  or  4),  falling  as 
the  flower  opens;  petals  4-6  (or  more),  imbricated,  often  crumpled  in 
the  bud,  and  early  falling;  stamens  usually  many;  ovary  1-  to  many- 
ovuled,  1-celled:  fruit  a  dry  pod  or  capsule,  1-celled  or,  in  Poppy, 
imperfectly  many-celled,  generally  dehiscing  by  a  pore  or  by  valves. 
Small  family  of  mostly  small  but  usually  showy  herbs. 

a.  Plants  with  white  (milky)  juice 1.  Papaver 

aa.  Plants  with  colorless  juice  (watery) 2.  Eschscholtzia 

aaa.  Plants  with  red  or  orange  juice. 

b.  Flower-bud  erect:  flowers  white,  in  earliest  spring.  .  .  .3.  Sanguinaria 
bb.  Flower-buds  generally  nodding;  flowers  yellow. 

c.  Stigma  3-4-lobed,  on  a  short  style.    Capsule  ovoid. 4.  Stylophorum 
cc.  Stigma  2-lobed,  about  sessile:  capsule  long 5.  Chelidonium 

1.  PAPAVER.    Poppy. 

Herbs  with  white  juice:  stems  smooth  or  hairy,  erect,  and  the  terminal 
buds  nodding,  but  erect  in  flower  and  fruit:  sepals  2  (or  3)  soon  falling;  petals 
4-6;  sessile  stigmas  united  to  form  a  rayed  disk. 

P.  somniferum,  Linn.  Opium  poppy.  Annual,  erect  to  13^-2  ft., 
branching,  glaucous,  with  large,  white  or  purplish-centered  flowers  on  long 
peduncles:  leaves  sessile,  clasping,  variously  incised:  capsule  smooth. 
Cultivated  for  opium  and  for  ornament. 

P.  Rhceas,  Linn.  Corn  poppy.  Shirley  poppy.  Annual,  bristly,  hairy, 
the  leaves  deeply  lobed:  flowers  mostly  red  or  scarlet  with  a  dark  center, 
varying  in  cultivation:  pod  small. 

P.  oriental e,  Linn.  Stem  rough-hairy,  1-flowered:  flowers  very  large, 
brilliant,  scarlet:  leaves  scabrous,  deep  green,  about  pinnate.  A  favorite 
perennial  in  gardens. 

P.  nudicaule,  Linn.  Iceland  poppy.  Rather  delicate,  hairy,  with  leaves 
radical,  pale  green,  and  pinnately  incised:  flowers  single,  on  slender,  hairy 
scapes,  orange  or  white.    Gardens. 

2.  ESCHSCHOLTZIA. 

Annual  or  perennial  herbs:  leaves  glaucous,  finely  pinnatifid:  sepals  2, 
cohering  as  a  pointed  cap,  falling  as  flower  opens;  petals  4,  yellow  or  orange 


PAPAVERACE.E — FUMARIACE^E  363 

or  cream-colored;  stamens  many,  adherent  to  petals;  stigmas  2-G,  sessile: 
pods  long,  cylindrie,  grooved,  many-seeded. 

E.  calif ornica,  Cham.  California  poppy.  Cultivated  in  flower-gardens: 
stem  branching,  leafy:  flowers  showy  and  large,  receptacle  funnelform, 
with  a  broadly  dilated  rim:  pod  long  and  slender.    California. 

3.  SANGUINARIA.    Bloodroot. 

Low,  acaulescent  perennial,  from  thick,  horizontal,  pointed  and  scarred 
rootstocks,  with  juice  red  and  acrid:  in  very  early  spring  a  naked  scape, 
carrying  1  terminal  white  flower,  enfolded  at  first  by  long-petioled  kidney- 
shaped  or  cordate,  glaucous,  palmately  veined  leaf;  sepals  2,  soon  falling; 
petals  8-12,  unequal,  in  2  rows,  not  lasting;  stamens  many:  fruit  a  capsule, 
oblong,  swollen,  1-celled,  many-seeded,  2-valved,  dehiscent  at  base. 

S.  canadensis.  Linn.  Flower  large,  white,  fragile,  on  a  scape  about  G 
in.  tall:  glabrous  and  glaucous:  leaves  with  rounded  lobes  and  sinuses. 
Common  in  rich,  open  woods  and  on  sunny  banks;  early  spring. 

4.  STYLOPHORUM.    Celandine  Poppy. 

Hairy  herbs  with  yellow  juice,  and  pinnately  divided  leaves:  flowers 
large,  yellow:  style  1:  stigma  3-4-lobed. 

S.  diphyllum,  Nutt.  Low  perennial,  usually  with  two  opposite,  pinnately 
parted  leaves  on  the  stem;  leaves  often  marked  with  white,  5-7-lobed: 
flowers  few,  in  umbels,  large,  1H_2  in.  across,  clear  yellow.  Frequent  in 
rich  woods  in  central  states.    May. 

5.  CHELIDONIUM.    Celandine. 

Rather  weak,  branching  herbs;  perennial:  leaves  alternate,  pinnatifid: 
juice  deep  yellow:  flowers  yellow,  small,  the  bud  nodding;  sepals  2;  petals 
4;  stamens  many. 

C.  majus,  Linn.  Along  roadsides,  about  fences,  as  a  weed,  growing  1-4 
ft.  high:  leaves  thin,  once  or  twice  pinnatifid:  flowers  in  loose  umbels, 
soon  perishing,  about  xA-3/\  in.  in  diameter. 


XIX.  FUMARIACE.E. 

Smooth,  succulent  herbs  with  noticeably  delicate,  finely  dissected, 
or  lace-like  leaves,  alternate  or  radical,  exstipulate:  flowers  small, 
irregular,  racemose;  2  very  small  sepals,  scale-like;  petals  4,  small, 
partially  united:  G  diadelphous  stamens  (2  sets  of  3  each);  ovaries 
1-celled:  fruit  a  pod,  1-celled,  1-seeded  and  indehiscent,  or  Beveral- 
seeded  with  2  parietal  placentae. 

a.  Corolla  2-spurred  at  base,  or  heart-shaped:  fls.  pendent. ...  1.  Die*  ntra 
aa.  Corolla  with  1  spur  at  base. 

B.  Pod  slender,  several-seeded:  seeds  arilled,  or  crested     .  .    2.  <'<iri/dalis 
bb.   Pod  globular,  1-seeded,  indehiscent 3.  Fumaria 


364  THE    KINDS    OF    PLANTS 


1.  DICENTRA. 

Low,  acaulescent  perennials,  among  the  earliest  and  most  delicate  of 
spring  flowers:  leaves  compound  in  3's,  finely  dissected  (lace-like),  on 
tender  pinkish  petioles  from  the  roots:  the  racemose,  nodding  flowers  borne 
on  leafless,  flesh-colored  scapes;  pedicels  2-bracted;  corolla  peculiarly 
irregular — 4  petals  in  2  pairs,  the  2  outer  spurred  at  base,  somewhat  united 
to  form  a  2-spurred  corolla,  the  inner  pair  of  petals  spoon-shaped,  crested, 
meeting  over  the  pistil  and  stamens;  stamens  6,  in  two  sets,  opposite  the 
outer  petals. 

D.  Cucullaria,  Bernh.  Dutchman's  breeches.  Leaves  from  a  cluster  of 
little  pinkish  tubers,  forming  a  bulb:  flowers  with  straight  spurs,  longer 
than  pedicel,  and  diverging,  mostly  creamy  with  yellow  tips  to  petals,  not 
fragrant. 

D.  canadensis,  Walp.  Squirrel  corn.  Similar  to  the  preceding,  but 
leaves  usually  glaucous:  root-tubers  yellow,  resembling  grains  of  Indian 
corn:  flowers  differing  in  shape  from  D.  Cucullaria  in  being  more  elongated, 
spurs  short  and  rounded,  and  the  crests  of  the  inner  2  petals  prominent: 
fragrant.  Blooms  a  little  later  than  preceding,  but  found  in  same 
situations. 

D.  spectabilis,  DC.  Bleeding-heart.  A  smooth,  leafy-stemmed  plant  of 
many  gardens;  stems  much  branching;  leaves  large,  twice  ternately  com- 
pound: flowers  many  and  showy  in  long  racemes  drooping  from  the  curv- 
ing stems,  heart-shaped,  bright  rose  or  pink;  no  sepals  when  in  full  flower. 
Siberia. 

2.  CORtfDALIS. 

Biennial  or  perennial  herbs  with  leafy  stems,  pale  or  glaucous:  leaves 
much  divided  or  decompound:  flowers  small,  in  racemes;  corolla  4-petaled, 
irregular;  one  of  the  outer  pair  of  petals  spurred  at  the  base,  all  erect  and 
somewhat  united. 

C.  sempervirens,  Pers.  Stem  slender,  erect,  6  in.  to  2  ft. :  leaves  small,  ses- 
sile above,  all  finely  dissected:  flowers  horizontal  in  terminal  racemes;  spurs 
short  and  blunt;  corolla  rosy,  yellow-tipped;  outer  petals  sharp-pointed:  pods 
erect,  slender.    May  to  June. 

C.  aurea,  Willd.  Low,  diffuse  or  spreading:  flowers  yellow,  XA  in.  long; 
outer  petals  keeled,  not  crested;  spur  shorter  than  pedicel  {l/i  in.),  decurved: 
pods  hanging  or  spreading,  knotty.    March  to  May. 

3.  FUMARIA.    Fumitory. 

Annuals,  branched  and  leafy-stemmed :  leaves  compound,  finely  dissected: 
flowers  small,  in  dense  racemes  or  spikes;  petals  4,  unequal,  1-spurred  at 
base;  stamens  6,  diadelphous:  fruit  small,  globular,  1-seeded,  indehiscent, 
the  style  falling. 

F.  officinalis,  Linn.  Low,  much  branched,  erect  to  1  ft.,  glabrous:  flowers 
purple-tipped,  pinkish,  minute,  in  loose  spikes;  sepals  acute,  sharply  toothed, 
shorter  than  corolla.    Waste  places.    Summer.    Introduced. 


MUSTARD    PLANTS  365 


XX.  CRUClFERiE.    Mustard  Family. 

Herbs,  mostly  of  small  stature,  with  alternate  mostly  simple  leaves: 
flowers  4-merous  as  to  envelopes,  the  4  petals  usually  standing  90 
degrees  apart  and  thereby  forming  a  cross  (whence  the  name  Cruciferse, 
or  "cross-bearing");  stamens  usually  6,  2  of  them  shorter:  fruit 
a  silique  or  silicle.  A  very  natural  or  well-marked  family,  with  about 
180  genera  and  nearly  2,000  species.  Familiar  plants  are  mustard, 
shepherd's  purse,  honesty,  cress,  pepper-grass,  wallflower,  stock, 
cabbage,  turnip,  radish,  horse-radish. 

a.  Fruit  a  silique  (much  longer  than  broad). 

b.  Silique  tipped  with  a  long  point  or  beak,  extending 

beyond  the  valves,  the  latter  more  than  1-nerved. .    1.  Brassica 
bb.  Silique  not  prominently  beaked  beyond  the  valves. 

c.  Flowers  yellow 2.  Barbarea 

cc.  Flowers  white  or  purple. 

d.  Valves  with  a  midrib,  or  6eeds  in  2  rows. 

e.  Stigma  deeply  2-lobed:  flowers  large 3.  Matthiola 

ee.  Stigma  but  slightly,  if  at  all  2-lobed 4.  Arabis 

dd.   Valves  without  midrib. 
e.  Seeds  in  1  row. 

F.  Stems  leafless  below,  with  2  or  3  leaves  near 

middle:  rootstock  scaly 5.  Dcntaria 

ff.  Stems  leafy:  roots  more  fibrous 6.  Cardamine 

ee.  Seeds  in  2  rows  in  each  cell.'  (Water  plants. 
See  Radicula.) 
aa.  Fruit  a  silicle  (short  and  broad). 

b.  Partition  in  the  pod  parallel  to  the  sides. 

c.  Fruit   not  much   compressed:   seeds  minute,   in   2 

rows  in  each  cell 7.  Radicula 

CC.   Fruit  quite  flattened,  2-8-secded 8.  Alyssum 

bb.   Partition  crosswise  the  pod. 

c.  Pod  obcordate,  many-seeded '.».  Capsi  Ua 

cc.  Pod  orbicular,  2-seeded:  corolla  regular 10.  Le  iridium 

ccc.  Pod   rounded   or  ovate:   corolla   irregular  with  un- 
equal petals 1 1 .  I  In  ria 

aaa.  Fruit    fleshy,    indehiscent,    constricted    between    the 

seeds 12.  Raphanua 

1.  BRASSICA.    Mustard. 

Erect  branchy  herbs,  mostly  annual,  with  more  or  less  lyrate  lower 
leaves,  and  small  yellow  flowers  in  racemes  or  panicles:  petals  clawed  or 
narrowed  below,  the  limbs  spreading  horizontally:  silique  narrow,  cylindrical 
or  4-angled,  the  valves  1-5-nerved  and  the  seeds  in  1  row  in  each  locule. 
Cabbage,  cauliflower,  and  turnip  also  belong  to  this  genus.  The  three  fol- 
lowing are  common  weeds  introduced  from  Europe: 


366  THE    KINDS    OF    PLANTS 

B.  nigra,  Koch.  Black  mustard.  Fig.  518.  Leaves  pinnatifid,  some- 
what hairy:  pod  short,  strongly  4-angled,  not  hairy.  Mustard  (flour)  comes 
largely  from  this  species. 

B.  alba,  Boiss.     White  mustard.     Leaves  pinnatifid,  and  rough -hairy: 
pods  rather  slender,  hairy,  but  only  the  lower  part  seed-bearing. 

B.  arvensis.  Kuntze.  Charlock.  Leaves  strongly  toothed, 
pod  knotty,  hairy  or  smooth,  the  upper  third  indehiscent  and  2- 
edged.    Fig.  413. 

2.  BARBAREA.   Winter  Cress. 

Low  herbs,  blooming  in  early  spring,  with  many  small  light 
yellow  flowers,  and  lyrate  leaves  with  the  terminal  division  much 
the  largest:  pod  cylindrical  or  somewhat  4-angled,  the  valves 
having  a  strong  midvein:  seeds  a  single  row. 

B.  vulgaris,  R.  Br.  Common  winter  cress.  Yellow  rocket. 
Biennial,  about  1  ft.  high,  with  smooth  foliage  and  flowers  in 
elongating  clusters:  lower  leaves  lyrate,  upper  ones  cut  or  merely 

toothed.    Low  grounds. 
or». 
Brassica      3    MATTHiOLA.   Stock.   Gilliflower. 
nigra. 

Cultivated  garden  or  house  plants  from  Europe:  stems  and 
leaves  hoary-pubescent:  flowers  showy,  single  or  double,  of  many  colors, 
fragrant,  in  terminal  racemes;  stigma  deeply  2-lobed:  silique  nearly  cylin- 
drical, with  prominent  midrib  on  each  of  the  2  valves;  seeds  winged. 

M.  incana,  R.  Br.  Biennial  or  perennial  with  stout,  rather  woody  stem: 
leaves  lanceolate,  entire:  flowers  white,  varied  shades  of  red,  purple,  etc. 
Much  grown  in  gardens  and  greenhouses. 

4.  ARABIS.   Rock  Cress. 

Mostly  very  small  herbs  with  purple  or  white  flowers:  stems  leafy:  rad- 
ical leaves  spatulate,  the  stem-leaves  sessile:  siliques  very  narrow,  elongated, 
flat,  the  valves  smooth,  keeled  or  one-nerved  in  the  middle,  or  veined  length- 
wise; seeds  in  1  or  2  rows  in  each  cell,  flattened,  usually  margined  or  winged. 

A.  canadensis,  Linn.  Sickle-pod.  Biennial  with  stems  erect,  1-3  ft.: 
leaves  lanceolate,  pointed  at  both  ends,  simple,  toothed  or  entire,  sessile, 
pubescent:  flowers  small,  white,  petals  twice  as  long  as  sepals:  pods  long, 
flat,  sickle-shaped,  pendent  on  hairy  pedicels;  seeds  broadly  winged.  Com- 
mon in  woods  and  rocky  ravines. 

A.  glabra,  Bernh.  Biennial  tall,  2-4  ft.,  glaucous  above,  but  pubescent 
at  base,  with  many  stem-leaves,  ovate-lanceolate,  6essile,  sagittate-clasping 
at  base;  petals  yellowish  white,  scarcely  longer  than  the  calyx:  pods  narrow, 
erect:  seeds  in  2  rows,  marginless.    Fields  and  rocky  places. 

5.  DENTARIA.   Toothwort. 

Low  herbs,  perennial,  found  in  damp  woodland,  blooming  with  the  early 
spring  flowers,  bearing  flowers  in  corymbs,  white,  roseate  or  purplish, 
larger  than  the  similar  flowers  of  Cardamine:  rootstocks  long,  horizontal, 


MUSTARD    PLANTS  367 

scaly  or  toothed,  aromatic  or  with  cress-like  taste:  stems  erect,  unbranched, 
leafless  below,  with  2  or  3  palmately  divided  or  compound  leaves  on  petioles; 
near  the  middle:  fruit  a  linear  silique,  flattened,  valves  not  nerved,  with  1 
row  of  seeds  in  each  cell;  seeds  not  winged. 

D.  diphylla,  Michx.  Crinkle-root.  Pepper-root.  Stem  erect,  from  a 
toothed  rootstock:  leaves  usually  2:  leaflets  3-parted,  wide-ovate,  with 
margins  dentate:  flowers  white. 

D.  laciniata,  Muhl.  Fig.  266.  Rootstock  deep,  short,  tuberous,  con- 
stricted in  several  places  (necklace-like):  stem-leaves  3,  nearly  verticillate, 
deeply  3-parted  into  lanceolate,  linear  or  oblong  Leaflets,  which  are  lobed  or 
toothed,  and  some  2-cleft:  flowers  white  or  pinkish,  smaller  than  preceding. 

6.  CARDAMINE.    Bitter-cress. 

Very  similar  to  Dentaria,  the  chief  difference  being  in  the  stem,  which 
is  leafy,  and  the  leaves  simple,  usually  more  or  less  lobed,  alternate  on  stem. 
Glabrous  perennials,  growing  in  wet  places  and  along  waterways,  from 
fibrous  roots  or  tubers  (not  scaly  rootstocks),  the  flowers  white  or  purple  in 
terminal  racemes. 

C.  bulbosa,  BSP.  Stem  simple,  erect,  9-18  in.,  from  a  tuber:  leaves 
simple,  petioled  below,  ovate  or  rhombic-oblong  in  shape:  petals  white, 
small,  much  longer  than  calyx.  A  variety  purpurea,  not  so  tall  (4-6  in.), 
with  rose-colored  flowers,  appears  even  earlier  than  the  type. 

7.  RADICULA.    Water-cress.    Horse-radish. 

Low,  mostly  aquatic  or  marsh  plants,  with  pinnate  or  pinnatifid  leaves 
(sometimes  simple);  flowers  small,  white  or  yellow,  with  spreading  sepals; 
stamens  1-6:  fruits  various,  short  and  broad  (silicle)  or  short-cylindrical: 
valves  convex,  nerveless  or  1-nerved.    Formerly  called  Nasturtium. 

R.  Nasturtium-aquaticum,  Britten  &  Rendle.  Water-cress.  Glabrous, 
growing  in  or  about  water:  stems  spreading,  rooting  at  the  nodes:  leaves 
pinnately  lobed,  with  3-11  lobes,  the  terminal  segment  largest:  flowers 
small  in  racemes,  which  elongate  as  the  fruits  mature:  petals  white  and  twice 
as  long  as  the  sepals.    A  favorite  plant  for  salads. 

R.  palustris,  Moench.  Marsh-cress.  Annual  or  biennial,  with  simple, 
fibrous  roots:  stem  erect,  1-2  ft.,  glabrous  or  slightly  pubescent:  pinnately 
lobed  leaves,  the  upper  sessile:  flowers  small,  yellow:  pods  oblong  or  ovoid, 
turgid,  1  it  tit-  if  any  longer  than  the  pedicels.    Weed  in  marshy  places. 

R.  Armoracia,  Robinson.  Horse-radish.  Cultivated,  but  sometimes 
escaped  into  waste  grounds:  perennial,  the  roots  long  and  thick:  root-leaves 
large,  coarse,  glabrous,  oblong,  crenate,  rarely  pinnatifid,  on  thick  petioles, 
the  stem  leaves  sessile,  lanceolate:  flowers  small,  petals  white,  longer  than 
calyx. 

8.  AL? SSUM.   Alyssdm. 

Small  plants,  mostly  trailing,  with  entire  and  small  leaves:  pod  small, 
orbicular,  1  or  2  seeds  in  each  locule:  flowers  in  elongating  racemes. 


368  THE    KINDS    OF    PLANTS 

A.  maritimum,  Linn.  Sweet  alyssum  of  the  gardens  (from  Europe). 
Fig.  519.  Annual,  producing  a  profusion  of  small  white,  fragrant  flowers. 
There  are  many  cultivated  forms. 

9.  CAPSELLA.    Shepherd's  Ptjrse. 

Low  short-lived  annuals,  with  very  small  white  flowers  in  racemes: 
pod  obcordate  or  inversely  triangular,  the  partition  run- 
ning across  the  narrow  diameter,  containing  several  seeds. 
C.  Bursa-pastoris,  Medic.  Common  shepherd's  purse. 
Fig.  286.  One  of  the  commonest  little  weeds:  root-leaves 
pinnatifid  or  strong-toothed,  in  a  rosette,  the  stem-leaves 
arrow-shaped.    Europe. 


LEPIDIUM.    Pepper-grass. 

Small  stifnsh  annuals  (or  biennials),  which  shed  their 

,,    leaves  late  in  the  season:  flowers  very  small,  white  or 

A/J^y?  V^ST^^     greenish,  in  elongating  racemes:  pod  small  and  roundish, 

the  partition  running  across  the  narrow  diameter.    Plant 

peppery  to  the  taste. 

519.  Alyssum  ^   yirginicum,  Linn.    Common  pepper-grass.     About 

1  ft.  high,  much    branched,  glabrous:   leaves   linear   to 

lanceolate,  tapering   to    the    base,  the  lower  mostly  pinnatifid.    Common 

weed;  often  fed  to  canary  birds. 

11.  IBERIS.    Candytuft.    Fig.  192. 

Herbs  with  white,  or  purple  flowers  in  flat  or  elongated  clusters;  2  outer 
petals  larger  than  2  inner:  silicles  flattened,  truncate,  cells  1-seeded.  Cul- 
tivated. 

I.  umbellata,  Linn.  Annual,  1  ft.  or  more:  lower  leaves  lanceolate,  the 
upper  linear  and  entire:  flowers  mostly  purple  or  lilac  in  flat  clusters: 
silicles  acutely  2-lobed.    June  and  July. 

I.  amara,  Linn.  Annual:  leaves  lanceolate,  toothed  toward  apex:  flowers 
white.  The  common  white-flowered  candytuft,  in  many  forms  (including 
the  garden  /.  coronaria). 

12.  RAPHANUS.   Radish. 

Annual  or  biennial  herbs,  with  lyrate,  pinnately-lobed  root-leaves: 
flowers  rather  showy  in  long  racemes;  calyx  erect;  petals  clawed;  style  long 
and  slender:  pod  linear,  indehiscent,  constricted  between  the  seeds,  pithy; 
seeds  spherical.    Europe. 

R.  Raphanistrum,  Linn.  White  charlock.  A  weed,  common  in  the 
East:  tap-root  slender:  petals  yellow,  fading  to  white  or  purplish:  pod  4-  to 
10-seeded,  long-beaked,  constricted  between  seeds  when  dry. 

R.  sativus,  Linn.  Garden  radish.  Flowers  pink  or  white:  root  fleshy, 
spindle-  or  turnip-shaped,  red  or  white:  silique  2-3-seeded,  short  and 
pointed,  with  fleshy  partitions  between  seeds:  seeds  round  and  blackish. 


369 


XXI.  VIOLACE.E.   Violet  Family. 


Ours  herbs  with  or  without  stems,  and  simple,  entire  or  cleft  leaves, 
radical  or  alternate,  with  stipules:  flowers  showy,  irregular,  solitary 
on  peduncles;  sepals  persistent;  petals  unequal,  the  lower  one  larger 
or  spurred  at  base;  stamens  with  filaments  short,  broad,  continued 
beyond  the  anthers,  usually  coherent,  joining  over  and  around  the 
pistil;  ovary  simple,  1-celled,  3  parietal  placentae:  fruit  a  3-valved 
capsule,  loculicidal,  and,  after  dehiscence,  edges  strongly  inrolled  in 
drying,  thus  dispersing  the  seeds.   One  genus  is  well  known. 

ViOLA.   Violets.   Heart's-ease.   Johnny-jump-up.   Fig.  236. 

Early  flowers  conspicuous  and  petaliferous,  but  frequently  sterile;  some- 
times later  flowers  cleistogamous,  concealed  under  the  leaves,  apetalous 
and  self-fertilized,  usually  developing  seeds;  sepals  eared  at  base;  petals 
unequal,  the  lower  spurred  or  saccate  at  base;  stamens  5,  2  with  spurs  which 
project  into  the  corolla  spur. 

a.  Stemless:  leaves  basal:  flowers  on  peduncles  from  rootslocks. 
b.  Flowers  blue  or  violet:  side  petals  beardless. 

V.  pedata,  Linn.  Bird's-foot  violet.  Not  stoloniferous,  rootstock  short, 
stout,  nearly  smooth:  leaves  orbicular  in  outline,  but  palmately  3-  or  5-11- 
lobed  or  divided,  segments  linear  not  lanceolate:  flowers  large,  1  in.  broad, 
pale  violet  or  deep  purple  (varying  to  white);  stigma  large,  not  beaked. 
Sandy  soil.  Var.  bicolor  has  2  upper  petals  deep  velvety  violet,  3  lower  pale 
blue. 

bb.  Flowers  blue  or  violet:  side  petals  bearded. 

V.  palmata,  Linn.  Common,  or  early  blue  violet.  Pubescent  to  nearly 
glabrous:  rootstock  stout  and  scaly:  early  leaves  rounded,  cordate  or  kidney- 
shaped,  margin  crenate,  the  later  leaves  various,  palmately  or  pedately 
lobed  or  parted,  on  long  stalks:  flowers  deep  or  pale  blue;  spur  short, 
saccate;  stigma  beaked. 

V.  cucullata,  Ait.  Common  blue  violet.  A  common  form,  variable  and 
grading  into  V.  palmata:  leaves  not  lobed  or  toothed  at  base,  merely  crenate 
or  dentate,  kidney-form  to  broadly  ovate:  nearly  or  quite  glabrous. 

V.  sagittata,  Ait.  Leaves  sagittate-lanceolate,  or  often  cordate,  toothed 
near  base:  scapes  bearing  the  flowers  shorter  than  the  leaves,  3-5  in.; 
sometimes  all  petals  bearded;  stigma  beaked;  flowers  usually  large. 

V.  odorata,  Linn.  Sweet  violet.  English  violet.  Hardy,  cultivated 
species  from  Europe:  stoloniferous  by  creeping  runners:  leaves  downy  or 
glabrous,  rounded  or  heart-shaped  or  broadly  ovate:  flowers  fragrant,  single 
or  double,  sometimes  white. 

bbb.  Flowers  while. 

V.  lanceolata,  Linn.  Rootstock  smooth,  creeping:  stoloniferous:  leaves 
lanceolate  to  linear,  erect,  the  blade  decurrent  on  the  long  petioles:  flower 


370  THE    KINDS    OF    PLANTS 

small,  white,  the  lower  and  side  petals  purplish-veined:  petals  beardless 
cleistogamous  flowers  on  erect  pedicels,  frequently  from  stolons.  Wet 
places. 

V.  blanda,  Willd.  Sweet  white  violet.  Stoloniferous  from  slender  root- 
stock:  flowers  fragrant:  petals  beardless  or  nearly  so,  white  veined  with 
purple:  leaves  cordate  or  rounded:  few  cleistogamous  flowers  on  curved 
stalks.   Wet  places.   Plant  small. 

bbbb.  Flowers  yellow. 
V.  rotundifolia,  Michx.    Stoloniferous:  leaves  rounded  to  cordate,  mar- 
gin somewhat  crenate,  finally  growing  large,  glossy  and  lying  flat  on  the 
ground:  flowers  small:  lateral  petals  bearded,  °nd  with  brown  lines;  sepals 
blunt-pointed.    Cool  woodlands. 

aa.  Stems  evident,  leafy:  flowers  showy  on  axillary  stalks. 
b.  Flowers  blue  or  violet. 

V.  rostrata,  Pursh.  Plant  3-8  in. :  leaves  rounded  heart-shaped,  serrate, 
the  upper  acuminate:  stipules  fringe-toothed,  lanceolate:  flowers  pale  violet, 
darker-veined:  petals  beardless:  spur  slender,  longer  than  corolla.  Moist 
woodland  and  shaded  hillsides. 

V.  arenaria,  DC.  Stems  weak,  6-8  in.,  glabrous:  leaves  heart-shaped 
or  kidney-form,  margin  crenate:  stipules  lanceolate,  somewhat  fringe- 
toothed:  spur  slender,  half  as  long  as  corolla.  Swamps  and  wet  places. 
Pale  purple.    American  forms  differ  from  the  European. 

bb.  Flowers  white,  tinged  with  pink  or  violet. 
V.  canadensis,  Linn.    Upright,  6  in.  to  2  ft. :  stems  leafy,  stipules  broad- 
lanceolate,  entire:  leaves  large,  heart-shaped,  serrate:  petals  white  inside, 
pinkish  or   violet  beneath,   spurred    petal   yellow  at  base:   lateral  petals 
bearded.   Common.    Rich  woods.    All  summer. 

bbb.  Flowers  yellow. 
V.  pubescens,  Ait.    Downy  yellow  violet.    Pubescent:  stems  erect,  5-20 
in.,  leafy:  leaves  broadly  heart-shaped,  toothed:  stipules  large,  entire:  root- 
leaves  soon  wither  up:  lower  petals  veined,  more  or  less  obscurely,  with 
purple;  spur  short;  stigma  beakless:  pod  downy.    Dry  woods. 

bbbb.  Flowers  of  various  colors:  cultivated 
V.   tricolor,   Linn.     Garden   pansy.     Stems   angular,    branching,   leafy: 
leaves  roundish  to  cordate:  stipules  leaflike,  incised:  flowers  widely  varied 
in  colors.    Europe.    Var.  arvensis,  in  fields,  is  slender,  and  petals  scarcely 
exceeding  sepals. 

XXII.  HYPERICACE.E.   St.  John's-wort  Family. 

Herbs  or  shrubs  (in  our  species),  with  leaves  chiefly  sessile,  sim- 
ple, opposite,  some  with  translucent  or  black  dots:  flowers  regular, 
usually  in  terminal  cymes,  and  yellow;  sepals  and  petals  4  or  5;  sta- 


HYPERICACEiE — PORTULACACEiE  371 

mens  few  to  many,  often  in  clusters  of  3  or  5,  hypogynous:  pod  1-  to 
7-celled. 

HYPERICUM.   St.  John's-wort.   Figs.  208,  278. 

Mostly  branching  plants  with  yellow  flowers  in  cymes:  leaves  sessile, 
usually  dotted:  sepals  and  petals  5;  stamens  many,  mostly  in  3-5  groups. 

H.  perforatum,  Linn.  A  common  introduced  species:  stems  upright, 
1-3  ft.,  branching,  2-edged:  leaves  linear  to  oblong,  dotted,  sessile:  flowers 
about  1  in.  in  diameter,  the  petals  dotted  with  black  and  much  exceeding  the 
lanceolate  sepals;  stamens  grouped  in  3  sets:  capsule  3-celhd.  Spreads 
by  running  shoots  from  base. 

H.  punctatum,  Lam.  Much  like  preceding,  but  leaves  more  broadly- 
oblong,  sepals  more  ovate,  and  the  petals  often  lined,  as  well  as  dotted,  with 
black. 

XXIII.  PORTULACACE^.   Purslane  Family. 

Herbs  succulent  or  fleshy,  with  entire  leaves,  alternate  or  oppo- 
site, and  dry  stipules:  flowers  regular  but  not  symmetrical;  sepals  2; 
petals  4-5  or  none;  stamens  equal  to  number  of  petals  and  opposite, 
or  fewer,  or  more;  ovaries  free,  each  1-celled;  style  2-3-cleft,  or  di- 
vided, stigmatic  on  inner  surfaces:  fruit  a  1-celled  pod,  opening  loculi- 
cidally,  or  a  pyxis,  opening  by  a  lid;  seeds  small,  kidney-shaped,  few 
or  many. 

A.  Stamens  more  numerous  than  petals:  flowers  opening  once 

only,  in  sunshine 1.  Portulaca 

aa.  Stamens  5:  flowers  open  for  some  time 2.  Claytonia 

1.  PORTULACA.    Purslane.    Fig.  280. 

Low,  fleshy  annuals,  diffuse  or  ascending:  terminal  flowers,  which  open 
once  only,  in  sunshine;  sepals  2,  joined  at  base  and  partially  adherent  to 
ovary;  petals  4-6  on  calyx,  not  lasting;  stamens  7  to  many,  on  calyx;  style 
3-8-parted. 

P.  oleracea,  Linn.  Common  purslane.  Pusley.  A  very  common  weed. 
Smooth,  fleshy,  prostrate:  stems  cylindrical,  reddish:  leaves  obovate  or 
wedge-form,  thick,  nearly  sessile:  flowers  small,  yellow,  sessile,  open  in 
morning  sunshine.    Sometimes  used  for  greens. 

P.  grandiflora,  Lindl.  Rose-moss.  Stems  erect,  3-6  in.,  fleshy,  smooth 
or  hairy:  leaves  alternate,  cylindrical,  ££— 1  in.  long:  flowers  open  in  morn- 
ing; very  gay  colors,  white,  yellow,  reds,  1-2  in.  wide.  South  America. 
Gardens. 

2.  CLAYTONIA.   Spring  Beauty. 

Low,  glabrous,  perennial  herbs,  from  small  tubers:  flowers  iasting  some 
time;  sepals  2;  petals  5,  distinct  or  slightly  united;  stamens  5,  1  on  base 
of  each  petal;  style  3-lobed;  ovary  1-celled:  capsule  3-valved,  few-seeded: 


372  THE    KINDS    OF    PLANTS 

6tcm  erect,  usually  bearing  2  leaves  and  terminating  in  a  raceme.  Among 
the  first  spring  flowers  in  open  woods. 

C.  virginica,  Linn.  Leaves  thickish,  linear-lanceolate,  3-6  in.  long, 
nearly  sessile:  stem  about  3  in.  from  tuberous  root,  bearing  2  (3  or  4  occa- 
sionally) leaves:  petals  white  or  pink  with  darker  veins,  emarginate  XA~% 
in.  long;  sepals  and  petals  obtuse. 

C.  caroliniana,  Michx.  Leaves  1-2  in.  long,  oblong  or  oval  to  spatulate, 
ehort-petioled :  flowers  fewer  than  in  preceding,  white  or  pinkish,  veined. 


XXIV.  MALVACEAE.    Mallow  Family. 

Herbs  or  shrubs  (trees  in  the  tropics)  with  alternate,  mostly  simple 
leaves  which  have  stipules:  flowers  perfect  and  regular,  5-merous, 
often  subtended  by  a  calyx-like  involucre,  the  petals  5;  stamens 
many,  united  in  a  column  which  closely  surrounds  the  several  styles; 
ovaries  several,  connivent  into  a  ring  or  sometimes  united  into  a  com- 
pound pistil,  in  fruit  making  1-seeded  1-loculed  more  or  less  indehis- 
cent  carpels  or  a  several-loculed  capsule.  About  60  genera  and  700 
species.  Representative  plants  are  mallow,  hollyhock,  abutilon,  hibis- 
cus, althea,  okra,  cotton. 

a.  Anthers  borne  only  at  the  top  of  the  stamen-tube. 

b.  Fruits  1-seeded,  forming  a  ring  at  the  base  of  the  styles. 

c.  Involucre  of  3  bracts 1.  Malva  ■ 

cc.   Involucre  of  6-9  bracts 2.  Althaea 

bb.  Fruit  of  several-seeded  carpels 3.  Abutilon 

aa.  Anthers  borne  all  along  the  side  of  the  stamen-tube 4.  Hibiscus 

1.  MALVA.    Mallow. 

Herbs,  with  a  3-leaved  involucre  like  an  extra  calyx;  petals  obcordate; 
carpels  many  in  a  ring,  separating  at  maturity,  1-seeded  and  indehiscent: 
leaves  usually  nearly  orbicular  in  general  outline. 

M.  rotundifdlia,  Linn.  Common  mallow.  Cheeses.  Fig.  248.  Trailing 
biennial  or  perennial,  rooting;  leaves  orbicular,  indistinctly  lobed,  toothed: 
flowers  small,  white  or  pinkish,  clustered  in  the  axils.  Yards  and  roadsides; 
from  Europe.    A  common  weed. 

2.  ALTHEA.   Marsh  Mallow. 

Differs  from  Malva  chiefly  in  having  a  6-9-cleft  involucre. 
A.  rosea,  Cav.     Hollyhock.    Figs.  222,  223,  263.    Tall  perennial,  with 
angled  or  5-7-lobed  cordate  leaves,  and  large  flowers  in  many  colors.    China. 

3.  ABUTILON.    Indian  Mallow.    Fig.  182. 

Mostly  shrubs,  often  with  maple-like  leaves,  and  no  involucre  to  the 
flower:  ovaries  and  fruits  several-seeded.  Contains  conservatory  plants. 
Fig.  520. 


MALVACEAE — GERANIACE^E  373 

A.  striatum  var.  Thompsonii,  Veitch.  Spotted  flowering  maple. 
Shrub:  leaves  3-5-lobed  but  more  typically  5-7-lobed,  green:  flowers 
drooping,  on  long  solitary  axillary  peduncles,  bell-shaped,  veiny-orange  or 
red.  A  conservatory  and  house  plant.  Several  forms  are  in  cultivation, 
probably  cultural  variations  from  the  tropical  American  type. 

A.  Theophrasti,  Medic.  Velvet  leaf.  Indian  mallow.  Stout 
annual,  3  or  4  ft.,  densely  pubescent:  flowers  yellow,  erect,  on 
peduncles  shorter  than  the  long  petioles:  leaves  large,  roundish 
heart-shaped,  taper-pointed,  and  velvety:  calyx  5-cleft;  carpels 
12-15,  united,  pubescent,  beaked,  2-valved,  with  3-9  seeds  in. 
each  cell.   August  to  October.    Weed,  from  Asia. 

4.  HIBISCUS.    Rose  Mallow. 

Herbs    or    shrubs,   with    an    involucre    of    many    narrow     520.  Garden 
bracts:    stamen-column    anther-bearing   most   of    its   length: 
styles,  5,  united:    pod  5-loculed,  loculicidal:    flowers  large  and  showy. 

H.  syriacus,  Linn.  Althea  of  cultivated  grounds.  Rose  of  Sharon. 
Shrub  10  ft.:  leaves  wedge-ovate  and  3-lobed:  flowers  showy,  in  various 
colors,  in  the  leaf-axils  in  summer  and  fall,  often  double.   Asia. 


XXV.  GERANIACE.E.   Geranium  Family. 

Herbs,  chiefly  with  simple  leaves:  flowers  perfect,  in  most  genera 
nearly  regular  (but  sometimes  very  irregular),  5-merous;  stamens  as 
many  or  twice  as  many  as  the  sepals,  hypogynous;  ovary  single,  the 
locules  usually  as  many  as  the  sepals:  fruit  capsular.  A  most  diverse 
family,  often  divided  into  several.  There  are  about  20  genera  and  700 
species.  Common  examples  are  geranium,  pelargonium,  nasturtium, 
balsam,  jewel-weed  or  touch-me-not,  oxalis. 
A.  Flowers  regular  or  very  nearly  so. 
B.  Leaves  simple  (often  deeply  lobed). 

c.  Anther-bearing  stamens  10 1.  Geranium 

cc.  Anther-bearing  stamens  about  7 2.  Pelargonium 

bb.  Leaves  compound 3.  Oxalis 

aa.   Flowers  very  irregular. 

B.  Flower  with  one  very  long  spur 4.  Tropseolum 

bb.  Flower  hanging  by  its  middle,  with  a  short  hooked  spur.5.  Impatiens 

1.  GERANIUM.    Cranesbill. 

Small  herbs  with  forking  stems  and  1-3-flowered  peduncles:  sepals  and 
petals  5;  glands  on  the  torus  5,  alternating  with  the  petals;  stamens  10, 
usually  all  of  them  with  perfect  anthers:  fruit  5  1-seeded  carpels  separat- 
ing from  the  axis  from  the  base  upwards  and  curling  outwards. 

G.  maculatum,  Linn.  Common  wild  cranesbill.  Fig.  195.  Perennial,  1-2 
ft.,  hairy  erect:  leaves  orbicular,  deeply  5-7-parted:  petals  entire,  hairy 
on  the  claw:  flower  rose-purple,  1  in.  across.    Common;  spring. 


374  THE    KINDS    OF    PLANTS 

G.  Robertianum,  Linn.  Herb  Robert.  Annual  or  biennial,  1  ft.  or  some- 
times less,  somewhat  hairy,  spreading:  leaves  3-  or  5-divided  into  pinnatifid 
divisions:  fls.  J^  in.  or  less  across,  pink-red.    Moist  places;  common. 

2.  PELARGONIUM.    Geranium  of  gardens. 

Somewhat  fleshy,  strong-scented  plants,  differing  from  Geranium  in 
having  a  somewhat  2-lipped  corolla,  and  stamens  with  anthers  less  than  10. 

P.  hortorum,  Bailey.  Garden  geranium.  Fish  geranium.  Fig.  39.  Stem 
somewhat  succulent  and  hairy:  leaves  orbicular  or  reniform,  crenate-lobed, 
often  with  bands  of  different  colors:  flowers  in  umbel-like  clusters,  deflexed  in 
bud  of  many  colors,  often  double.    South  Africa,  but  of  hybrid  origin. 

P.  peltatum,  Ait.  Ivy-leaved  geranium.  Trailing:  filaments  10,  some 
being  sterile:  petals  pink  or  white,  nearly  equal:  leaves  more  or  less  peltate, 
nearly  or  quite  smooth,  5-angled  or  -lobed. 

P.  fragrans,  Willd.  Nutmeg  geranium.  Stems  somewhat  shrubby, 
and  the  branches  straggling,  thick,  and  softly  haiiy:  leaves  small,  rounded, 
very  downy,  fragrant:  flowers  small,  white. 

P.  graveolens,  Ait.  Rose  geranium.  Somewhat  shrubby:  filaments  10, 
some  sterile:  leaves  divided  palmately,  the  5  or  7  lobes  more  or  less  toothed, 
revolute  and  rough-edged:  petals  not  equal,  but  2  upper  larger:  flowers 
umbelled,  small,  pinkish-lavender,  veined  with  darker:  plant  very  fragrant. 

3    OXALIS.    Ox-alis.    Wood-sorrel. 

Low  often  tuberous  herbs  with  small  flowers  which  have  no  glands  on 
the  torus-disk:  leaves  digitate,  of  3  or  more  leaflets,  usually  mostly  radical: 
flowers  (opening  in  sun)  with  5  sepals  and  petals  and  10  somewhat  mona- 
delphous  stamens,  the  alternate  ones  shorter:  pod  5-loculed,  often  opening 
elastically.    The  following  have  3  obcordate  leaflets,  closing  at  night. 

O.  stricta,  Sav.  Common  yellow  oxalis.  Fig.  300.  Stem  leafy  and  branch- 
ing: peduncles  bearing  2-6  small  yellow  flowers.    Common  in  fields. 

O.  Acetosella,  Linn.  Wood-sorrel.  Scape  2-5  in.  high,  from  a  creeping 
rootstock:  flowers  white  and  pink-veined.    Deep  woods. 

O.  violacea,  Linn.  Scape  5-10  in.  high  with  an  umbel  of  several  bright 
violet  flowers,  from  a  scaly  bulb.  Woods  South,  and  a  common  window- 
garden  plant. 

4.  TROP-dEOLUM.   Nasturtium  of  gardens. 

Tender,  mostly  climbing  herbs  (by  means  of  leafstalks),  with  one  of  the 
5  petals  extended  into  a  long,  nectar-bearing  yellow  spur:  petals  usually  5, 
with  narrow  claws,  often  bearded;  stamens  8,  of  different  shapes;  carpels 

3,  indehiscent  in  fruit.    The  following  (from  Peru)  have  peltate  orbicular 
leaves  (Fig.  140). 

T.  ma  jus,  Linn.  Climbing  nasturtium.  Tall-climbing:  flowers  yellow, 
red,  cream-white,  and  other  colors;  petals  not  pointed. 

T.  minus,  Linn.  Dwarf  nasturtium.  Fig.  211.  Not  climbing:  petals 
with  a  sharp  point. 


GERANIACE^E — SAPINDACE^E 


375 


5.  IMPATIENS.    Touch-me-not.    Jewel-weed. 

Soft  or  succulent  tender  herbs  with  simple  alternate  or  opposite  leaves 

and  very  irregular  flowers:  sepals  3  to  5,  usually  4,  one  of  them  produced 

into  a  large  curving  spur;  petals  apparently  2,  but  each 

consisting    of  a  united   pair;   stamens   5:    fruit   5-valved, 

elastically  discharging   the   seeds  (whence  the  names  "Ini- 

patiens"  and  "touch-me-not"). 

I.  Balsamina,  Linn.    Garden  balsam.    Erect  and  stout, 

1-2 Y2  ft.:  leaves  lanceolate,  toothed:  flowers  in  the  axils, 

of  many  colors,  often  full  double. 

I.  biflora,  Walt.    (/.  fulva,  Nutt.).    Orange  jewel-weed.    T 

'       ,  ..  ,  '     „    .       .  ,       .  Impatiens  biflora. 

Fig.  521.      I  all   branching  plant    (2-4  ft.)  with  alternate 

oval  or  long-oval  blunt-toothed  long-stalked  leaves:  flowers  Y\  in.  long, 
horizontal  and  hanging,  orange-yellow  with  a  red-spotted  lower  lip,  the 
upper  lip  less  spotted  and  of  one  piece,  the  2  green  sepals  at  the  apex  of 
the  pedicel  closely  appressed  to  the  tube,  the  tail  of  the  spur  curled  under 
the  spur:  pod  opening  elastically  when  ripe,  throwing  the 
seeds  (the  5  valves  quickly  curling  from  above  down- 
wards).   Common  in  swales. 

I.  pallida,  Nutt.  (I.  aiirea,  Muhl.).  Yellow  jewel-weed. 
Fig.  522.  Leaves  usually  stronger-toothed,  the  teeth  usu- 
ally ending  in  sharp  points:  flowers  1  in.  long  and  much 
broader  than  those  of  /.  biflora,  clear  yellow,  the  upper  lip 
of  two  parts,  the  lower  also  of  2  parts  and  nearly  hori- 
zontal, the  2  sepals  at  apex  of  pedicel  large  and  not  closely 
522.  appressed,  tail  shorter:  pods  as  in  the  other.    Less  common 

Impatiens  pallida,    than  the  other,  but  often  growing  with  it. 


XXVI.  SAPINDACE.E.   Soapberry  or  Maple. 

Trees  or  shrubs,  of  various  habit:  flowers  polypetalous  or  apeta- 
lous,  often  inconspicuous,  4-  or  5-merous:  stamens  10  or  less,  borne 
on  a  fleshy  ring  or  disk  surrounding  the  single  2-3-loculed  pistil:  fruit 
a  pod  or  samara.  A  various  family,  largely  tropical.  Genera  about  75 
and  species  about  600-700.  Maple,  box-elder,  buckeye,  horse-chest- 
nut, bladder-nut,  are  familiar  examples. 
a.  Herb:    climbing    by    hook-like    tendrils    among    the 

flowers  in  the  cluster:  fruit  an  inflated  pod 1.  Cardiospermum 

aa.  Trees  and  shrubs. 

b.  Stature  of  trees  (or  tall  shrubs). 

c.  Leaves    simple    (more    or    less    palmately    lobed) 
or    (in    1    species)    3-5    pinnatcly    compound: 

fruit  a  samara  (with  2-winged  seeds) 2.  Acer 

cc.  Leaves  digitately  compound,  5-9  leaflets 'A.  MscuLut 

bb.  Stature  of  shrubs:  leaves  pinnately  3-7  compound: 

fruit  a  large  bladdery  pod 4.  Staphylea 


376  THE    KINDS    OF    PLANTS 

1.  CARDIOSPERMUM.    Balloon-vine.    Heart-seed. 

Vines  climbing  by  axillary,  hook-like  tendrils  among  flower-clusters: 
leaves  alternate,  biternate,  leaflets  toothed:  flowers  dioecious,  or  some  per- 
fect; sepals  4,  2  of  them  smaller;  petals  4,  irregular,  each  with  an  appendage 
at  inner  base;  stamens  8,  filaments  un- 
equal; style  short,  3-cleft;  ovary  triangular, 
3-celled,  1  ovule  to  each  cavity:  capsule 
membranous,  much  inflated. 

C.  Halicacabum,  Linn.  Climbing 
or  spreading  herb,  delicate  and  slender: 
leaflets  ovate-lanceolate,  acute,  cut  and 
toothed:  flowers  small,  white:  fruit  large, 
balloon-like,  decorative;  seeds  black  with 
523,  '524  white     scar,     hard,     round.      Cultivated. 

Acer  saccharinum.     Acer  rubrum.    Summer. 

2.  ACER.    Maple.    Box-elder. 

Trees  or  shrubs,  with  opposite  lobed  or  parted  leaves  (pinnate  in  box- 
elder):  flowers  small  and  greenish  or  reddish,  in  early  spring  and  often 
from  winter  buds,  in  box-elder  dioecious,  in  true  maples  perfect  (or  imperfectly 
diclinous);  calyx  about  5-cleft;  petals  5  or  none;  stamens  usually  3-8:  fruit 
a  samara  with  2  seeds  and  2  wings.  Two  shrubby  woods  maples  are  common 
in  some  parts  of  the  country. 

a.  Maples:  leaves  simple,  palmately  lobed. 

b.  Flowers  from  lateral  winter  buds,  preceding  the  leaves:  fruit 

maturing  very  early. 

A.  saccharinum,  Linn.  (A.  dasycdrpum,  Ehrh.).  While  or  silver  maple. 
Fig.  523.  Flowers  greenish,  with  no  petals:  leaves  very  deeply  5-lobed, 
silvery  white  beneath,  the  narrow  divisions  lobed  and  toothed:  fruit  with 
large  spreading  wings,  downy  when  young.  Common  along  streams  and  in 
low  grounds;  much  planted.  There  is  a  cut-leaved  form  known  as  Wier's 
maple,  popular  as  a  lawn  tree.  Wood  white.  Linnaeus  thought  it  to  be  the 
sugar  maple,  hence  his  name  "saccharinum." 

A.  rubrum,  Linn.  Red,  soft,  or  swamp  maple.  Fig.  524.  Tree  usually 
of  only  medium  size:  flowers  red,  with  narrow- 
oblong  petals:  leaves  rather  small,  not  deeply 
3-5-lobed,  whitish  beneath,  the  lobes  serrate 
and  toothed:  fruit  with'nearly  parallel  or  slightly 
spreading  wings,   not  downy.     Low  grounds. 

bb.  Flowers  in  clusters,  with  the  leaves,  some 

or  all  on  shoots  of  the  season.  525.    Acer  saccharum. 

A.  saccharum,  Marsh.  (A.  saccharinum  of  some).  Sugar,  hard,  or  rocA: 
maple.  Figs.  143,  525.  Flowers  greenish,  drooping,  on  long  pedicels,  the 
petals  none  and  the  calyx  hajry  at  the  top:  leaves  bright  green,  firm,  cordate- 
orbicular  in  outline,  3-lobed  and  the  side  lobes  again  lobed,  all  lobes  and 


MAPLES  377 

teeth  ending  in  points,  the  basal  sinus  broad  and  open:  wings  of  fruit  some- 
what spreading.    Commonest  of  maples  East. 

A.  nigrum,  Michx.  Black  sugar  maple.  Fig.  526.  Foliage  dark  and  limp, 
the  lobes  broad  and  shallow,  little  toothed  and  with  only  blunt  points,  the 
basal  sinus  nearly  or  quite  closed:  wings  of  fruit  nearly  parallel,  large. 
Eastern  Central  States;  by  some  regarded  as  a  form  of  A.  saccharum. 

A.  plantanoides,  Linn.  Xorway  maple.  Figs.  79,  80,  157,  323-330.  Flowers 
late,  in  umbel-like  clusters,  yellowish  green,  large,  with  both  sepals  and 
petals:  leaves  large  and  heavy,  3-5-lobed  and  much  toothed,  all  parts  ending 
in  points:  fruit  with  wide-spreading  wings.  Europe.  Commonly  planted: 
has  milky  juice. 

A.  Pseudo-platanus,  Linn.  Sycamore  maple.  Tree  from  Europe,  and 
many  varieties  cultivated:  leaves  broad,  3-7-lobed,  glabrous  above,  whitish 
and  downy  below;  lobes  acute,  unequally  toothed:  racemes  terminal,  droop- 
ing; flowers  yellowish-green;  ovaries  woolly:  fruit  downy,  the  wings  rather 
spreading. 

bbb.  Flowers  appearing  after  the  leaves,  in  racemes:  large  bushes  or 
bushlike  small  trees  in  cool  woods  and  ravines. 

A.  pennsylvanicum,  Linn.  Striped  maple.  Moose-wood.  Bark  smooth- 
ish,  light  green,  striped:  flowers  greenish,  in  ter- 
minal drooping  loose  racemes:  leaves  simple, 
thin,  3-lobed  near  apex,  the  lobes  acuminate, 
with  finely  toothed  margin  all  around:  fruit 
greenish,  smooth,  with  large,  widely  diverging 
wings.   Small  tree. 

A.  spicatum,  Lam.  Mountain  maple.  Shrub,  526    Acer  nigrum 

5-10  ft.,   usually  forming  clumps:  bark  green, 

not  striped:  flowers  appearing  after  leaves,  in  dense  racemes,  upright, 
compound,  small,  greenish:  leaves  slightly  3-5-lobed,  coarsely  serrate:  fruit 
with  narrow,  somewhat  divergent  wings. 

aa.  Box-elder:  leaves  pinnate. 
A.  Negundo,  Linn.  {Negundo  aceroides,  Moench).  Box-elder.  Tree  with 
green  glaucous  twigs  and  leaf-bases  covering  the  buds:  flowers  in  long 
racemes,  dicecious,  with  4-5-cleft  calyx  and  no  corolla,  and  4-5  stamens,  the 
sterile  flowers  on  long,  slender  pedicels:  leaves  pinnate,  with  3-5  ovate- 
pointed  toothed  leaflets:  fruit  with  somewhat  incurving  wings.  Common; 
much  planted  in  cold  and  dry  regions  west. 

3.  jESCULUS.    Horse-chestnut.    Buckeye. 

Trees:  leaves  opposite,  on  long  petioles,  palmately  compound,  5-7-folio- 
late:  flowers  irregular,  in  a  terminal  panicle,  some  often  imperfect,  most  of 
them  with  some  imperfect  pistils  and  stamens;  calyx  5-toothed;  corolla 
irregular,  with  4  or  5  clawed  petals;  stamens  5-8,  usually  7:  fruit  a  leathery 
capsule,  smooth  or  spiny,  2-3-valved,  each  valve  containing,  usually,  1  seed 
only;  seed  large,  with  shiny  brown  coat  and  a  large,  round,  pale  scar;  not 
edible. 


378  THE    KINDS    OF    PLANTS 

M.  Hippocastanum,  Linn.  Common  horse-chestnut.  Fig.  277.  Buds 
noticeably  large  and  resinous:  leaf-scars  large,  horseshoe-shaped:  leaves 
large,  palmately  compound,  usually  with  7  leaflets;  leaflets  obovate,  abruptly 
pointed  at  tip:  corolla  of  5  petals,  white,  spotted  with  purple  and  yellow; 
stamens  long,  exserted:  fruit  prickly.    Blooms  June  to  July. 

M.  rubicunda,  Loisei.  Red  horse-chestnut.  Small,  round-headed  tree, 
cultivated:  leaflets  5-7:  petals  4,  broad,  on  slender  claws,  rose-red;  stamens 
usually  8. 

EL.  glabra,  Willd.  Ohio  buckeye.  Tall  tree,  native  in  woods  and  along 
river  banks,  west  of  Alleghanies:  bark  rough  and  ill-scented  when  peeled  or 
bruised:  leaflets  5,  oval  or  oblong,  acuminate:  flowers  small,  in  short  panicle; 
petals  4,  narrow,  on  claws,  nearly  equal,  erect,  pale  yellow;  stamens  longer 
than  petals:  fruit  prickly  at  first.    April,  May. 

EL.  octandra,  Marsh.  Sweet  buckeye.  Large  tree,  rarely  shrubby:  bark 
dark  brown,  scaly:  leaflets  usually  5,  sometimes  7:  flowers  yellow;  calyx 
oblong;  petals  4,  very  unequal,  long-clawed,  connivent,  longer  than  sta- 
mens: fruit  glabrous.    Rich  woods  West  and  South.    April  and  May. 

EL.  Pavia,  Linn.  Red  buckeye.  Shrub  or  small  tree,  3-10  ft.,  found  in 
fertile  soil  West  and  South:  flowers  red;  calyx  tubular;  petals  4,  unequal, 
longer  than  the  stamens:  fruit  nearly  smooth. 

4.   STAPHYLFA.    Bladder-nut. 

Upright  shrubs  with  opposite  leaves,  pinnately  compound,  with  3-7  leaf- 
lets, stipulate:  flowers  small,  white,  in  drooping  clusters;  sepals,  petals  and 
stamens  5;  styles  2-3:  capsule  a  large  bladdery  pod,  2-3-lobed,  2-3-celled, 
each  cell  several-seeded. 

S.  trifolia,  Linn.  Shrub  6-10  ft.,  in  thickets,  in  moist  soil:  leaflets  3, 
ovate,  acuminate,  serrate,  stipules  deciduous:  flowers  bell-like,  white,  in 
clusters  at  ends  of  branchlets. 


XXVII.  POLYGALACE.E.   Milkwort  Family. 

Herbs  or  shrubs,  with  leaves  mostly  simple,  entire,  without  stipules, 
and  flowers  irregular  and  perfect.    Represented  by  the  genus 

POLYGALA.    Milkwort. 

Mostly  herbs,  with  bitter  juice:  flowers  very  irregular,  some  often  cleisto- 
gamous;  sepals  5,  unequal,  2  of  them  winged  and  colored  (petal-like);  petals 
3,  usually  united  into  a  tube,  the  middle  petal  hooded  or  crested,  or  other- 
wise appendaged;  stamens  6  or  8,  the  filaments  usually  monadelphous,  but 
the  sheath  split,  more  or  less  connate,  within  or  hidden  in  the  middle  petal; 
ovary  2-celled.  The  irregularity  of  the  flowers  makes  some  of  the  species 
conspicuous,  but  others  have  very  minute  flowers,  difficult  to  examine. 

P.  paucifolia,  Willd.  Fringed  polygala.  Flowering  wintergreen.  The 
most  striking  of  the  common  milkworts,  the  flower  being  large  (about  1  in. 
long)  and  showy,  rose-purple,  with  a  fine,  fringed  crest  on  the  central  corolla 


PEA    FAMILY  379 

lobe:  plant  low,  3-4  in.  high,  branching,  from  a  creeping  roots tock,  with 
oval  petiolate  leaves  clustered  near  the  tips  of  the  stems,  the  lower  leaves 
scale-like:  there  are  small,  whitish  and  fertile  (cleistogamous)  flowers  on  the 
rootstock.   In  moist,  rich  woodland.   East  and  North. 

P.  Senega,  Linn.  Seneca  snakeroot.  Flowers  small  in  terminal,  slender, 
spike-like  racemes:  stem  erect,  8-15  in.,  simple  and  leafy:  leaves  lanceolate, 
alternate:  flowers  white  or  greenish,  on  very  short  pedicels;  corolla  with 
small  crest.    Perennial. 


XXVIII.  LEGUMINOS^E.   Pulse,  or  Pea  Family. 

Herbs,  shrubs,  or  trees,  mostly  with  pinnately  compound  alter- 
nate leaves:  flower  papilionaceous  in  the  species  described  below: 
fruit  typically  a  legume.  A  vast  family  and  widely  dispersed,  with 
many  tropical  species.  Genera  about  400,  and  species  about  6,500. 
By  some  authors,  the  species  with  papilionaceous  flowers  are  separated 
into  the  family  Papilionacea?,  and  those  of  the  acacia  tribes,  with 
regular  flowers,  as  the  Mimosaceae.  Familiar  leguminous  plants  are 
pea,  bean,  lupine,  clover,  alfalfa,  vetch,  wistaria,  locust,  red-bud. 

a.  Shrubs,  twining 1.  Wisteria 

aa.   Trees,  or  erect  shrubs. 

B.  Leaves   once  or  twice   pinnately   compound:   flowers 
in  racemes:  often  large  trees. 
c.  Flowers    truly    papilionaceous,    rather    large    and 
showy,     usually     fragrant:     leaves     with     sharp 

spines  or  prickles  often  in  place  of  stipules 2.  Robinia 

cc.  Flowers    small,    greenish    and    inconspicuous,    not 
truly   papilionaceous:    tree    usually  armed  with 

large  pronged  thorns 3.  Gleditsia 

bb.  Leaves  simple,  entire:  corolla  not  truly  papilionaceous: 

fls.  in  umbel-like  clusters,  before  the  leaves 4.  Cercis 

aaa.  Herbs. 

B.  Plant  climbing  by  tendrils. 

c.  Calyx  leafy -lobed 5.  Pisum 

cc.  Calyx  not  leafy-lobcd. 

D.  Style  flattened,  bearded  down  1  side 6.  Lathyrus 

dd.  Style  slender,  with  a  tuft  of  hairs  at  apex  only, 

or  about  the  upper  part 7.  Vicia 

bb.  Plant  not  tendril-bearing:  leaves  compound. 

d.  The  leaves  3-foliolate  (sometimes  simple  in  No.  9). 
E.  Leaves  digitatcly  compound. 

F.  Stamens   diadelphous    (9   and    10),    and   the 

flowers  in  heads,  or  spikes 8.  Trifolium 

ff.  Stamens  10,  distinct:  flowers  in  racemes 9.  Baptisia 


380  THE    KINDS    OF    PLANTS 

ee.  Leaves    pinnately     compound     (terminal     1- 
stalked,  and  the  stalk  jointed),  3  leaflets. 
f.  Flowers  small,  in  a  long  raceme. 

g.  Pod    straight,    exceeding    calyx:    flowers 

small,  in  very  slender  racemes 10.  Melilotus 

gg.  Pods   curved   or  coiled:   flowers,  small  to 

medium,  in  heads  or  short  spikes 11.  Medicago 

ff.  Flowers  medium   to  large,   clustered   at  the 
ends  of  the  raceme. 
G.  Keel  of  the  corolla  coiled  into  a  spiral ....  12.  Phaseolus 

gg.  Keel  curved  but  not  coiled 13.  Vigna 

dd.  The  leaves  more  than    3-foliolate,  or    digitately 
compound. 

e.  Digitately  compound,  5-7  leaflets 14.  Lupinus 

ee.  Pinnately  compound. 

f.  Even-pinnately    compound:    many    leaflets: 

flowers  yellow 15.  Cassia. 

ff.  Odd-pinnate    (sometimes  3   leaflets)   of  5-7 

leaflets:  flowers  purplish  or  lavender 16.  Apios 

1.  WISTERIA. 

Tall  shrubby  twiner,  producing  long,  dense  racemes  of  showy  flowers: 
leaves  pinnate,  with  several  or  many  leaflets:  2  upper  cal^x-teeth  shorter: 
standard  large  and  roundish:  pod  knotty,  several-seeded. 

W.  chinensis,  DC.  Wistaria.  Popular  climber  for  porches,  from  China, 
with  large  drooping  racemes  of  bright  blue  (sometimes  white)  pea-like 
flowers  in  spring  and  summer. 

2.  ROBINIA.    Locust. 

Trees  or  large  shrubs  with  compound,  odd-pinnate  leaves,  with  stipules 
or  stipular  spines,  the  base  of  the  leaf-stalk  covering  the  next  year's  bud: 
flowers  showy,  pea-like,  hanging  in  axillary  racemes;  calyx  5-cleft;  standard 
of  the  corolla  large,  turned  back,  inclosing  side  petals  in  bud. 

R.  Pseudo-Acacia,  Linn.  Common  black  locust.  Tree,  native  West  and 
South,  everywhere  introduced  and  valuable  for  timber.  Bark  nearly  black, 
very  rough:  stiff  spines  at  base  of  each  leaf:  leaflets  9-19,  ovate  or  oval, 
somewhat  mucronate  at  tip,  on  short  stalks:  racemes  3-5  in.  long,  from 
axils,  pendulous,  slender  and  loose,  the  flowers  white,  very  fragrant:  pod 
smooth,  4-7-seeded. 

R.  viscosa,  Vent.  Small  tree,  native  to  southern  states:  cultivated:  leaf- 
stalks, branchlets  and  pods  glandular-viscid  (clammy):  prickles  short: 
flowers  roseate,  in  dense,  erect  racemes.    April  to  June. 

R.  hispida,  Linn.  Rose  acacia.  A  straggling  shrub,  to  10  ft.:  branches, 
stalks,  and  pods  bristly  with  flexible  red  spines:  flowers  pink,  handsome,  in 
loose  pendulous  racemes.  Native  of  southern  mountains.  Cultivated.  May 
to  June. 


PEA    FAMILY  381 

3.  GLEDfTSIA.   Honey  Locust. 

Trees,  thorny  with  stout  branching  spines  on  branches  and  usually  on 
trunk:  leaves  abruptly  pinnate,  frequently  bi-pinnate,  and  all  gradations 
often  on  same  leaf:  flowers  in  axillary,  spicate  racemes,  greenish,  inconspicu- 
ous, some  imperfect,  not  papilionaceous;  calyx-tube  short,  3-5  cleft;  petals 
3-5,  nearly  equal,  inserted  on  calyx-tube;  stamens  3-10,  distinct,  inserted  on 
petals:  fruit  a  large,  leathery,   flat  pod,   elongated,    containing    1   to   many 


G.  triacanthos,  Linn.  Large  tree  with  hard  and  heavy  wood:  pods  6-18 
in.  long,  an  inch  or  so  wide,  twisted  or  hoop-like,  filled  with  sweetish  pulp 
between  the  several  to  many  smooth,  shiny  seeds. 

4.  CERCIS.    Redbud. 

Small  trees  with  simple,  rounded,  heart-shaped  leaves  and  tiny  stipules 
soon  falling:  flowers  roseate-purple,  in  numerous  small  clusters  along 
branches,  even  on  trunk,  before  leaves,  thus  giving  the  tree  a  striking 
appearance;  calyx  5-toothed,  campanulate;  corolla  irregular,  not  papil- 
ionaceous; petals  5  and  standard  inclosed  by  wings;  stamens  10,  distinct: 
legume  oblong,  flat,  many-seeded,  margined  on  one  edge. 

C.  canadensis,  Linn.  Redbud.  Judas  tree.  Native  small  tree  of  middle 
and  southern  states,  10-30  ft.  high,  irregularly  branching:  bark  smooth  and 
dark.   Cultivated  as  ornamental  tree,  April,  May. 

5.  PiSUM.   Pea. 

Slender  herbs,  climbing  by  tendrils  which  are  homologous  with  leaflets: 
leaves  pinnate,  with  1-3  pairs  of  foliar  leaflets,  and  very  large,  leafy  stipules: 
lobes  of  calyx  leafy;  flowers  large,  white,  or  pink,  on  axillary  peduncles:  pod 
a  typical  legume,  several-seeded. 

P.  sativum,  Linn.  Garden  pea.  Figs.  206,  310.  Smooth  and  glaucous:  leaf- 
lets usually  2  pairs,  broad-oval:  peduncles  2-  or  more-flowered.  Old  World. 

6.  LATHYRUS.    Veitchling. 

Much  like  Pisum,  differing  chiefly  in  very  technical  characters,  but  best 
told  in  general  by  the  narrow  leaflets  and  pods,  and  not  leafy  calyx. 

L.  odoratus,  Linn.  Sweet  pea.  Figs.  177,  245.  Annual,  the  stem  hairy: 
leaflets  one  pair,  narrow-oval  or  oblong:  flowers  2  or  3  on  a  long  peduncle, 
very  fragrant,  in  many  colors.    Southern  Europe. 

L.  latifolius,  Linn.  Everlasting  pea.  Fig.  272.  Perennial  of  long  dura- 
tion, smooth,  the  stems  winged:  leaflets  one  pair,  long-oval:  flowers  many 
in  a  dense  cluster  on  long  peduncles,  rose-purple  and  white.    Europe. 

7.  VICIA.    Vetch.    Tahe. 

Herbs,  mostly  trailing  or  climbing  by  tendrils  from  the  ends  of  pin- 
nately    compound    leaves:    leaflets   usually   many,    entire   or   emarginate: 

stipules  half -sagittate:  flowers  in  axillary  racemes  or  pairs;  calyx  somewhat 
oblique,  5-toothed;  wings  adhering  to  keel;  style  slender,  bent,  hairy  or  with 
hairy  ring  beneath  stigma:  pods  flat,  2-valved,  2-  to  several-seeded. 


382  THE    KINDS    OF    PLANTS 

V.  americana,  Muhl.  Perennial,  smooth:  leaflets  10-14,  oblong,  blunt: 
peduncles  4-8-flowered:  flowers  purplish-blue,  lA~2A  in.   long.    Moist  soil. 

V.  Cracca,  Linn.  Perennial,  more  or  less  pubescent,  with  weak  stems: 
leaflets  12-24,  oblong  to  linear,  mucronate:  racemes  many-flowered,  1-sided, 
spike-like,  on  axillary  peduncles;  flowers  blue  to  purple,  M-J^  in.  long. 
Dryish  soil. 

V.  sativa,  Linn.  Spring  vetch.  Annual,  rather  pubescent,  not  climbing: 
leaflets,  5-7  pairs,  oblong  or  obovate,  to  linear,  obtuse  or  retuse  or  mucro- 
nate: flowers  in  pairs,  from  axils,  nearly  sessile,  violet-purple, zA-\  in.  long: 
pod  smooth,  linear,  5-10-seeded.    Cultivated  or  wild;  from  Europe. 

V.  villosa,  Roth.  Hairy  or  winter  vetch.  Diffuse,  very  hairy:  flowers 
showy  in  long  axillary  racemes,  deep  purple:  seeds  small  and  black.  Culti- 
vated and  escaped.  Europe.  Annual  and  biennial,  perhaps  sometimes 
perennial. 

8.  TRIFOLIUM.   Clover. 

Annual  or  perennial  herbs  with  digitate  leaves  of  3  leaflets  (all  3  leaflets 
joined  directly  to  top  of  petiole):  flowers  small,  with  bristle-form  calyx- 
teeth,  in  dense  heads:  fruit  a  1-  to  few-seeded  little  pod  which  does  not 
exceed  the  calyx. 

a.  Flowers  sessile  in  the  dense  heads. 
T.  pratense,  Linn.  Common  red  clover  Figs.  85,  173.  Erect, 
1-2  ft.,  with  oval  or  obovate  leaflets,  which  have  a  pale  spot 
or  band  near  the  center  and  usually  a  notch  at  the  end:  flowers 
rose-red,  honey-sweet,  the  heads  closely  surrounded  by  leaves. 
Europe,  but  common  everywhere  in  the  North. 

T.  medium,  Linn.  Medium  red  clover.  Larger,  the  stem  less 
straight,  the  leaflets  oblong,  entire  and  with  a  spot:  head  stalked 
above  the  uppermost  leaves.    Otherwise  like  the  last. 

T.    arvense,    Linn.     Rabbit-foot  clover.     Annual;  5-10    in., 
erect:  flowers  sessile  in  dense,  cylindrical  heads,  which  become 
very  soft  and  grayish  fur-like,   from  the  silky  plumose  calyx- 
Trifoiium    teeth;   corolla   insignificant,    whitish.    Dry,  sandy  soils;  intro- 
incarnatum.    duced  from  Europe. 

aa.  Flowers  short-stalked  in  the  heads. 

T.  hybridum,  Linn.  Alsike  clover.  Slender,  from  a  prostrate  base,  1-3 
ft.:  leaflets  obcordate:  head  small  and  globular,  light  rose-colored.    Europe. 

T.  repens,  Linn.  White  clover.  Small,  the  stems  long-creeping  and 
sending  up  flowering  stems  3-12  in.  high:  leaflets  obcordate:  heads  small, 
white.    Common;  native,  also  European. 

T.  incarnatum,  Linn.  Crimson  clover.  Fig.  527.  Stout,  hairy,  erect 
plant,  1-23^  ft.,  with  obovate-oblong  leaflets  and  brilliant  crimson  flowers 
in  a  long-stalked  head.    Europe;  now  frequently  cultivated. 

T.  refiexum,  Linn.  Buffalo  clover.  Annual  or  biennial,  pubescent,  ascend- 
ing 8-18  in. :  standard  purple,  keel  and  wings  whitish :  leaflets  oval  or  obovate, 
finely  toothed.    Most  common  in  central  states,  from  western  New  York. 


527. 


LEGUMINOS.E 


383 


T.  procumbens,  Linn.  Low  hop  clover.  Annual,  Blender,  procumbent 
>r  upright  to  6  or  12  in.:  flowers  yellow,  turning  brown  and  dry  when  old, 
finally  reflexing;  standard  striate;  heads  small,  rounded,  20  40-flowered: 
leaflets  wedge-shaped  and  notched  at  end,  terminal  one  stalked,  stipules 
ovate.    June.    Dry  soil,  introduced. 

T.  agrarium,  Linn.  Hop  clover.  Larger:  leaflets  ovate- 
oblong,  the  terminal  one  not  stalked,  and  stipules  narrow 
and  joined  for  half  their  length  to  the  petiole.    Introduced. 

9.  BAPTISIA.    False    Indigo. 

Perennial  herbs:  leaves  palmately  3-foliolate,  with 
stipules  (or,  simple,  sessile,  exstipulate,  perfoliate  leaves): 
flowers  racemed;  calyx  4-5-toothed;  standard  erect, 
rounded,  the  sides  rolling  back;  keel  and  wings  oblong, 
nearly  straight;  stamens  10,  distinct:  pod  stalked  in  a 
persistent  calyx,  pointed,  inflated,  many-seeded.  Plants 
usually  blackened  in  drying. 

B.  tinctoria,  R.  Br.  Bushy,  erect  to  2  ft.,  somewhat 
glacuous:  leaves  sessile  or  nearly  so,  with  tiny  deciduous 
stipules;  leaflets  small,  entire,  wedged-ovate:  racemes 
many,  terminal,  loosely  few-flowered;  flowers  yellow,  about 
x/2  in.  long,  papilionaceous.    Dry  soil  in  woods. 

10.  MELILOTUS.    Sweet  Clover. 

Tall,  erect  annuals    or    biennials,    with    sweet-scented 
herbage  and    small   white  or  yellow  flowers  in  numerous 
open  racemes:  leaflets,  3,  oblong:  pod  ovoid,  somewhat  exceeding  the  calyx, 
1-2-seeded. 

M.   alba,   Desr.     White  sweet  clover.    Bokhara  clover.     Fig.    184.     Two 
to  5  ft.  tall,  smooth:  leaflets  truncate:  flowers  white,  the  standard  longer  than 
other  petals.    Europe;  common  on  roadsides. 

M.  officinalis,  Lam.  Yellow  sweet  clover.  Fig.  528. 
Leaflets  obtuse:  flowers  yellow.  Less  common  than  the 
other. 

11.  MEDIC  AGO.    Medick. 

Clover-like  plants  with  small  flowers  in  heads  or 
short  spikes  and  toothed  leaflets:  particularly  distin- 
guished  by  the  curved  or  coiled  pod. 

M.  sativa,  Linn.     Alfalfa.     Lucerne.    Figs.  21,  246, 

529.     Erect  perennial,  with  ovate-oblong   leaflets  and 

short  spikes  or  dense  racemes  of  blue-purple  flowers. 

Europe.      Grown   extensively   for   forage,    being   made   into    hay   and    also 

ground  into  "alfalfa  meal." 

M.  lupulina,  Linn.  Black  medick.  Trailing  clover-like  plant,  with  obovate 
leaflets  and  yellow  flowers  in  heads  or  very  short  spikes:  pod  black  when 
ripe.    Europe;  common  weed  East. 


528.    Melilotus 
officinalis. 


529.  Medicago  sativa. 


384 


THE     KINDS    OF    PLANTS 


12.  PHASEOLUS.   Bean. 

Tender  herbs,  often  twining,  the  flowers  never  yellow,  and  the  pinnate 
leaves  of  3  leaflets:  flowers  usually  in  clusters  on  the  joints  of  the  raceme  or 
at  the  end  of  the  peduncle,  the  keel  (inclosing  the  essential  organs)  coiling 
into  a  spiral:  fruit  a  true  legume. 

P.  vulgaris,  Linn.  Common  bean.  Figs.  1,  308,  309, 
311,  312,  322,  530.  Annual:  twining  (the  twining  habit 
bred  out  in  the  "bush  beans"):  leaflets  ovate,  the  lateral 
ones  unequal -sided :  flowers  white  or  purplish,  the  racemes 
shorter  than  the  leaves:  pods  narrow  and  nearly 
straight.    Probably  from  tropical  America. 

P.  lunatus,  Linn.  Lima  bean.  Fig.  531.  Annual:  tall- 
twining  (also  dwarf  forms):  leaflets  large:  flowers  whit- 
ish, in  racemes  shorter  than  the  leaves:  pods  flat  and 
curved,  with  a  few  large  flat  seeds.    South  America. 

P.  multiflorus,  Willd.  Scarlet  runner  bean.  Perennial 
in  warm  countries  from  a  tuberous  root,  tall-twining: 
leaflets  ovate:  flowers  bright  scarlet  (white  in  the  "White  Dutch  Runner 
bean")  and  showy,  the  racemes  exceeding  the  leaves:  pod  long  and  broad 
but  not  flat.     Tropical  America;  cultivated  for  ornament  and  for  food. 


530. 

Phaseolus  vulgaris, 


13.   VfGNA.    Cowpea. 

Differs  from  Phaseolus  chiefly  in  technical   characters,  one 
of  which  is  the  curved  rather  than  coiled  keel  of  the  flower. 

V.   sinensis,     Endl.       Cowpea.      Black    pea.      Stock    pea.       v*» 
Figs.  273,  532.    Long-trailing  or  twining,  tender  annual:  leaf- 
lets narrow-ovate;  flowers  white  or  pale,  2  or  3  on  the  apex  of 


531.  Phaseolua 
lunatus. 


a  very   long   peduncle,   the   standard   rounded;   pod    slender 

and    long,  cylindrical:    seed   (really  a  bean  rather  than  pea) 

small,    short-oblong.     China,  Japan;    much  grown  South  for  forage,  and 

used  also  as  cover-crop. 


14.  LUPiNUS.   Lupine. 

Low  herbs:  leaves  palmately  compound,  5-15  foliolate,  rarely  simple: 
flowers  showy,  in  terminal  spikes  or  racemes:  calyx 
decidedly  2-lipped:  standard  round,  sides  rolled  back- 
ward: keel  incurved,  sickle-like:  wings  lightly  united 
above  keel:  stamens  monadelphous,  with  3  alternate 
anthers,  different  in  size  and  shape  from  others:  pod 
oblong,  flattened,  often  knotty. 

L.  perennis,  Linn.  Perennial,  somewhat  downy: 
stem  erect  to  1  or  1J^  ft.:  leaflets  7-11,  large,  radiat- 
ing, nearly  sessile,  oblanceolate,  mucronate;  stipules 
small:  flowers  blue  or  whitish,  in  loose  racemes:  pod 
linear-oblong,  hairy,  5-6-seeded.  Sandy  soil.  May  to 
June. 


LEGUMINOS^ — ROSACEA  385 

15.  CASSIA.    Senna.    Fig.  247. 

Our  herbs  with  odd-pinnate,  compound  leaves  and  yellow  flowers:  sepals 
5,  nearly  equal;  corolla  not  papilionaceous,  nearly  regular;  petals  5,  stamens 
5-10,  some  anthers  usually  imperfect:  pod  often  curved,  many-seeded. 

C.  marilandica,  Linn.  Smooth  perennial,  3-4  ft.:  leaflets  6  '■>  pairs,  lance- 
olate-oblong,  mucronate,  with  a  gland  at  or  near  base  of  petiole:  stipules 
deciduous:  stamens  10,  3  imperfect,  with  deformed  anthers,  the  anthers 
black:  flowers  showy  yellow,  short,  axillary  racemes.    Summer. 

10.   APIOS.    Groundnut. 

Perennial,  twining  herb,  with  edible  underground  tubers:  leaves  pin- 
nately  3-7-foliate:  flowers  in  short,  dense,  often  branching  axillary  racemes: 
calyx  rather  2-lipped:  standard  broad  and  reflexed:  keel  strongly  incurved, 
pushing  into  the  standard,  and  finally  coiled  or  twisted. 

A.  tuberosa,  Moench.  Flowers  brownish  purple,  sweet -scented,  in  dense 
racemes  about  1-3  in.  long:  no  tendrils:  juice  milky.  Summer.  In  low, 
moist  ground  and  shady  woods. 


XXIX.  ROSACEA.   Rose  Family. 

Herbs,  shrubs  and  trees,  much  like  the  Saxifragacese:  leaves 
alternate,  mostly  with  stipules  (which  are  often  deciduous):  flowers 
mostly  perfect  and  polypetalous,  the  stamens  usually  perigynous, 
mostly  numerous  (more  than  20);  pistils  1  to  many:  fruit  an  achene, 
follicle,  berry,  drupe,  or  accessory.  A  very  mixed  or  polymorphous 
family,  largely  of  temperate  regions,  of  about  75  genera  and  1,200 
species.  By  some  writers,  divided  into  three  or  four  families.  Common 
rosaceous  plants  are  rose,  strawberry,  apple,  pear,  plum,  peach,  cherry, 
blackberry,  raspberry,  spirea,  cinquefoil. 

a.  Herbs. 

b.  Torus  not  enlarging. 

c.  Carpels  many,  in  a  head. 

D.  Style  deciduous 1.  Potentilla 

dd.  Style  persistent  on  achene,   usually  jointed  and 

plumose • 2.  Geum 

cc.  Carpels   2:    calyx   prickly   and   lobes   closing  over 

the  fruit:  1  or  2  achencs 3.  Agrimonia 

bb.  Torus    becoming    fleshy:    flowers    directly    from    the 

crown  or  root 4.  Fragaria 

AA.  Shrubs  or  trees. 

b.  The  ovary  1,  superior:  fruit  a  drupe 5.  Prunus 

bb.   The  ovaries  more  than  1. 

c.  Fruit  1-seeded  drupes  aggregated,  or  achenes. 

Y 


386  THE    KINDS    OF    PLANTS 

d.  Ovaries  many,  free  from   calyx  and  torus,  be- 
coming drupelets 6.  Rubus 

dd.  Ovaries  5-8:  shrubs  not  prickly:  leaves  simple: 

flowers  yellow:  fruit  achenes 7.  Kerna 

cc.  Fruit  achenes  inside  a  hollow  torus 8.  Rosa 

ccc.  Fruit  a  pome:  ovaries  usually  5,  immersed  in  the 
torus. 
d.  Petals  oblong-spatulate:  carpels  3-5-celled,  but 

appearing  about  10-celled 9.  Amelanchier 

dd.  Petals  rounded :  ovaries  5. 

E.  Pome  with  2-seeded  carpels 10.  Pyrus 

ee.  Pome  with  many-seeded  carpels 11.  Cydonia 

eee.  Pome  with  1-5  stony  kernels 12.  Crataegus 

cccc.  Fruit  2-8  dry  follicles,  each  several-seeded 13.  Spiraea 

1.  POTENTILLA.    Five-finger.    Cinquefoil. 

Herbs  (sometimes  shrubby)  with  flat  deeply  5-cleft  calyx  and  5  bracts 
beneath  it,  and  5  obtuse,  mostly  yellow  or  white  petals;  stamens  many:  fruit 
an  achene,  of  which  there  are  many  in  a  little  head  on  the  small,  dry  torus: 
leaves  compound. 

P.  norvegica,  Linn.  An  erect  (1-2  ft.  tall)  very  hairy  and  coarse  annual, 
with  3  obovate,  or  oblong  serrate  leaflets  and  small  flowers  in  which  the  yel- 
low corolla  is  usually  not  so  large  as  the  calyx.    Common  weed. 

P.  canadensis,  Linn.  Common  five-finger.  Trailing,  strawberry-like 
with  5  narrow  leaflets,  but  the  lateral  ones  deeply  lobed:  flowers  solitary, 
on  axillary  peduncles,  bright  yellow.    Fields;  common. 

P.  argentea,  Linn.  Perennial,  with  stem  prostrate,  branching  above, 
white-woolly:  leaflets  5,  wedge-oblong,  green  above,  white-pubescent  beneath, 
with  a  few  large,  incised  teeth,  and  margins  revolute:  flowers  small,  cymose, 
yellow;  stamens  about  20.    June  to  September,  in  dry  soil. 

P.  fruticosa,  Linn.  Stem  erect  (1-2  ft.),  shrubby,  diffusely  branched: 
leaves  pinnate,  with  5-7  sessile  leaflets,  margins  entire,  revolute:  flowers 
axillary;  petals  yellow,  orbicular,  and  longer  than  calyx,  1  in.  broad. 
Marshy  and  wet  ground.   June  to  September. 

2.  GfiUM.   Avens. 

Perennial,  erect  herbs,  with  odd-pinnate  or  lyrate  leaves,  with  stipules: 
flowers  resembling  those  of  Potentilla;  calyx  5-cleft  with  5  alternate 
bracts;  stamens,  many:  achenes  numerous,  aggregated  on  a  conical  recep- 
tacle, with  long  persistent  styles  jointed,  or  bent,  or  plumose. 

G.  rivale,  Linn.  Stems  erect,  1-2  ft.,  several-flowered:  root-leaves 
lyrate,  and  irregularly  pinnate,  petioled:  stem-leaves  few,  usually  of  3 
leaflets,  or  3-lobed:  flowers  few,  large,  nodding,  the  calyx  purplish,  the 
petals  clawed,  erect,  yellowish  purple;  styles  purplish,  jointed  and  bent  in 
middle,  stigmas  plumose:  fruit  stalked  in  the  calyx.    May  to  July.    Bogs. 

G.  canadense,  Jacq.  From  2-3  ft.,  with  stem  erect,  branching,  smooth 
or  downy:  root-leaves  of  3-5  leaflets,  or  simple  with  smaller  leaflets  at  base: 


ROSE    TRIBES 


387 


533.  Fragaria  vesca. 


stem-leaves  few,  simple,  lobed,  or  3-divided  or  toothed  and  short-petioled: 
flowers  whitish,  the  petals  not  longer  than  sepals:  head  of  fruits  sessile  in 
the  calyx:  styles  jointed  and  bent  near  middle,  the  lower  part  hooked:  torus 
bristly.    Late  spring  and  summer. 

G.  virginianum,  Linn.    Differs  from  preceding  in  being  hirsute:   root- 
leaves    various,    but    pinnate,    with    a    very   large 
rounded   terminal   leaflet;    the   upper   leaves   mostly  ^- 
3-parted:    flowers  white   or  pale  yellow:    receptacle  ^aS* 
not   bristly;   heads   of   fruits  on  short,  stout,  hairy 
stalks.    Low  ground.    Summer. 

3.  AGRIMONIA.    Agrimony. 

Perennial,  erect  herbs,  with  alternate  odd-pin- 
nately  compound  leaves,  and  slender,  spike-like 
racemes,  with  yellow  flowers:  leaves  with  small  seg- 
ments interposed,  and  large  dentate  stipules:  calyx- 
tube  contracted  at  the  throat  with  a  5-cleft  limb,  and  bristly  on  upper 
part;  petals  5;  stamens  slender,  5-15,  carpels  2,  styles  terminal:  fruit  dry, 
included  in  the  prickly  calyx-tube. 

A.  gryposepala,  Wallr.   Spicate  raceme  terminating  the  stem  (6  in.  to  2  ft. 
high) ,  petals  yellow  and  twice  longer  than  the  calyx.   Dryish  soils.  Summer. 

4.  FRAGARIA.    Strawberry. 

Low  perennials  with  3  broad-toothed  leaflets  and  a  few  flowers  on  radical 
peduncles:  torus  enlarging  in  fruit,  usually  becoming  fleshy. 

F.  vesca,  Linn.    Fig.  533.    Small,  very  sparsely  hairy,  the  leaves  thin 

and  rather  light  green,  very  sharply  toothed:  flower-clusters  overtopping 

the  foliage,  small  and  erect,  forking:  fruit  slender  and  pointed,  light  colored 

(sometimes  white),  the  achenes  not  sunk  in  the  flesh.    Cool  woods;  common 

North. 

F.  virginiana,  Duch.  Common  field  strawberry. 
Fig.  534.  Stronger,  darker  green,  loose-hairy,  the 
leaves  with  more  sunken  veins  and  larger  and  firmer: 
flower-cluster  slender  but  not  overtopping  the  leaves, 
in  fruit  with  drooping  pedicels:  fruit  globular  or 
broad-conical,  with  achenes  sunk  in  the  flesh;  light 
colored.    Very  common. 

F.  chiloensis,  Duch.  Garden  strawberry.  Fig. 
291.  Low  and  spreading  but  stout,  the  thick  leaves 
somewhat  glossy  above  and  bluish  white  beneath, 
rather  blunt-toothed:  flower-clusters  short,  forking, 
the  pedicels  strong  and  long:  fruit  large  and  firm,  dark  colored,  with 
sunken  achenes.  Chile. 

5.  PRUNUS.   Peach.   Plum.    Cherry. 

Trees  and  shrubs,  mostly  floweriim  in  early  spring:  sepals,  petals  and 
stamens  borne  on  the  rim  of  a  saucer-shaped  torus,  the  calyx  with  5  green 


534.    Fragaria  virginiana. 


388 


THE    KINDS    OF    PLANTS 


spreading  lobes  and  the  petals  5  and  obovate;  pistil  1,  sitting  in  the  bottom 
of  the  flower,  the  ovary  ripening  into  a  drupe:  leaves  alternate. 

a.   Peach  and  apricot:  flowers  solitary  from  lateral  winter-buds,  usually 
appearing  before  the  leaves. 

P.  Persica,  Stokes.  Peach.  Fig.  535.  Small  tree,  with  oblong-lanceolate 
pointed  serrate  leaves  and  solitary  fuzzy  fruits  on 
last  year's  wood.  China.  The  nectarine  is  a 
smooth-fruited  form. 

P.  armeniaca,  Linn.  Apricot.  Figs.  69,  536. 
Leaves  ovate  to  round-ovate,  serrate:  fruits  solitary, 
on  last  year's  shoots  or  on  spurs,  smooth  or  nearly 

535.    Primus  persica.      so.    China. 

aa.  Plums:  flowers  in  umbel-like  clusters:  fruit  large  and  smooth,  usually 
with  a  distinct  suture  (or  "crease")  on  one  side  and  covered  with  a 
"bloom,"  the  stalk  short. 

P.  domestica,  Linn.  Common  plum.  Figs.  209,  289.  Small  tree,  usually 
with  young  shoots  downy:  leaves  thick  and  relatively 
large,  dull  dark  green,  ovate,  oval  or  obovate,  very  rugose 
or  veiny,  somewhat  pubescent  beneath,  coarsely  and  un- 
evenly serrate :  flowers  large:  fruits  various,  usually  thick- 
meated  and  with  heavy  "bloom."    Europe,  Asia. 

P.  americana,  Marsh.  Wild  plum  of  the  North.  Fig. 
537.  Twiggy  small  tree,  often  thorny,  the  young  shoots 
usually  not  downy:  leaves  obovate,  dull  green,  abruptly 
pointed,  coarsely  toothed  or  jagged,  not  pubescent  be- 
neath: fruit  small,  red  or  yellow,  tough-skinned  and  glau- 
cous, the  pit  large  and  flattened.  Common  in  thickets;  improved  forms  are 
in  cultivation.    Including  P.  nigra,  perhaps  distinct. 

P.  angustifolia,  Marsh.  Chickasaw  plum.  Mountain  cherry.  Fig.  538. 
Smaller,  the  young  growth  smooth  and  zigzag  and  usually  reddish:  leaves 
lanceolate  to  oblong-lanceolate,  often  trough-shaped,  shining,  finely  serrate, 
cherry-like:  fruit  a  small  thin-fleshed  shining  plum  on  a  long  pedicel. 
Delaware,  south;  also  in  cultivation. 


aaa.    Cherries:  flowers  in  umbel-like  clusters:  fruit 

small    and    nearly     globular,    early-ripening, 

usually    without    a    prominent     suture     and 

"bloom,"  the  stalk  slender. 

P.  Cerasus,  Linn.     Sour  cherry.     Round-headed 

tree,  with  flowers  in  small  clusters  from  lateral  buds: 

leaves    hard  and  stiffish,   short-ovate    or    obovate, 

grayish  green,  serrate:  fruit  small,  sour.    Europe. 

P.  Avium,  Linn.  Sweet  cherry.  Fig.  539.  Straight 
grower,  the  "leader"  prominent  in  young  trees,  with 
flowers  in  dense  clusters  from  lateral  spurs:  leaves 


Prunus 
armeniaca. 


Fim 


537.    Prunus  americana. 


PRUNUS — RUBUS 


389 


538.    Prunus  anguatifolia. 


oblong-ovate,  dull  and  soft,  on  the  yourm  growth  hanging:   fruit  usually 
rather  large,  sweet.    Europe. 

aaaa.   Wild  cherries,  with  small,  scarcely  edible  fruits: 
flowers  umbellate  or  racemed. 

P.  pennsylvanica,  Linn.  Wild  red  cherry.  Pin  or  bird  cherry.  Small 
tree,  20-30  ft.  high,  with  red-brown, 
peeling  bark:  flowers  small,  white,  on 
long  pedicels  in  umbel-like  clusters, 
from  lateral  scaly  buds,  in  early  spring, 
before  or  with  the  leaves:  fruit  very 
small,  globose,  red,  smooth,  with  thin, 
sour  flesh. 

P.  virginiana,  Linn.  Choke  cherry. 
Small  tree  or  shrub,  5-20  ft.,  with 
grayish  spotted  bark:  leaves  thin,  oval 
or  obovate,  abruptly  acute  at  tip, 
sharp-serrate:  flowers  white,  in  short 
racemes,  terminating  leafy  branches,  appearing  after  leaves  in  late  spring: 
fruit  small,  globose,  red  changing  to  dark  crimson  (nearly  black),  very 
astringent:  usually  found   along  banks  and  in  thickets. 

P.  serotina,  Ehrh.  Wild  black  cherry.  Tree,  50-80  ft.,  with  black,  rough 
bark  and  reddish  brown  branches:  leaves  thickish,  oblong  or  oblong-lanceo- 
late, acute  or  tapering  at  tip,  serrate  with  incurving  or  bluntish  teeth:  flow- 
era  later  than  preceding,  white,  in  elongated,  drooping  or  spreading,  termi- 
nal racemes:  fruit  deep  purple  or  black  (M  in.  in  diameter)  with  a  sweetish, 
bitter  taste. 

6.  RUBUS.    Bramble. 

Shrubs,  usually  thorny,  the  canes  or  shoots  dying  after  fruiting,  with 
alternate  digits tely  compound  leaves:  flowers  white,  in  clusters,  with 
5-parted  calyx  and  5  petals :  ovaries  many,  ripening  into  coherent  drupelets. 

a.  Raspberries:  drupelets  or  berry  separating  from  the  torus. 

R.  occidentalis,  Linn.  Black  raspberry.  Figs.  142, 
290.  Canes  long  and  thorny,  glaucous,  rooting  at  the 
tips  late  in  the  season:  leaves  of  mostly  d  ovate 
doubly-toothed  leaflets:  flowers  in  close,  umbel-like 
clusters:  fruits  firm,  black  (sometimes  amber-color). 
Woods,  and  common  in  cultivation. 

R.  aculeatissimus,  C.   A.   Meyer.     Red  raspbi  try. 
Canes  erect  and  weak-prickly,  more  or  less  glaucous, 
leaflets  oblong-ovate:  flowers  in  racemes:  fruits  soft, 
red.    Woods,  and  cultivated. 

R.  odoratus,  Linn.  Flowering  raspberry.  Flowering  "midberry."  Shrubby 
and  erect,  branching,  3-5  ft.,  not  prickly,  but  rather  bristly  and  sticky- 
hairy:    leaves   large,   3-5-lobed:   flowers   large,    1-2  in.   broad,   in   terminal 


539.    Prunus  Avium, 
not  rooting  at  tips. 


390  THE     KINDS     OF    PLANTS 

corymbs,  the  petals  orbicular  and  purplish  rose  (rarely  whitish):  fruit  red, 
ripe  in  August,  flattened,  sweetish  but  scarcely  edible.    Common  in  woods. 

aa.  Blackberries:  drupelets  adhering  to  the  torus  (the  torus  forming 
the  "core"  of  the  berry). 

R.  allegheniensis,  Porter  (R.  rillosus  of  some).  Common  blackberry. 
Tall,  very  thorny:  leaflets  3  or  5,  ovate  and  pointed,  toothed,  hairy  beneath: 
flowers  large,  in  open  racemes:  fruit  cylindrical  and  firm,  black  when 
ripe.    Woods,  and  cultivated. 

R.  villosus,  Ait.  (R.  canadensis  of  some).  Northern  dewberry.  Trail- 
ing and  rooting  at  tips,  prickly :  leaflets  3-7,  ovate-acuminate  or  oblong-ovate, 
toothed:  flowers  1-3,  on  erect,  short  peduncles,  large:  fruit  like  a  small  and 
shining  blackberry.    Sterile  fields,  and  in  cultivation. 

R.  trivialis,  Michx.  Southern  dewberry.  Fig.  170.  Long-trailing,  very 
thorny  and  bristly:  leaves  3-5,  more  or  less  evergreen,  mostly  lance-oblong 
and  small,  strong-toothed:  flowers  1-3:  fruit  black.  Sands,  Virginia,  south; 
also  in  cultivation. 

7.  KERRIA.   Globe  Flower.    "Japan  Rose." 

Shrubby  plants  with  calyx  of  5  acuminate,  nearly  distinct  sepals;  petals 
5  (or  flowers  double);  ovaries  5-8,  smooth,  globose:  leaves  simple,  ovate, 
acuminate,  doubly  serrate,  with  stipules:  flowers  terminal  on  branches,  soli- 
tary or  a  few  together. 

K.  japonica,  DC.  Bush  3-8  ft.  with  green  winter  twigs:  flowers  orange- 
yellow,  usually  double:  leaves  sometimes  variegated.  Late  May  and  June. 
Cultivated. 

8.  ROSA.    Rose. 

More  or  less  thorny  erect  or  climbing  shrubs  with  pinnate  wing-petioled 
leaves,  and  flowers  with  5  calyx-lobes  and  5  large,  rounded  petals:  pistils 
many,  becoming  more  or  less  hairy  achenes  which  are  inclosed  in  a  hollow 
torus  (fruit  becoming  a  hip,  Fig.  292).  Most  of  the  garden  roses  are  too 
difficult  for  the  beginner:  they  are  much  modified  by  the  plant-breeder. 

R.  Carolina,  Linn.  Swamp  rose.  Tall,  often  as  high  as  a  man,  the  few 
spines  usually  somewhat  hooked:  stipules  (petiole  wings)  long  and  narrow: 
leaflets  5-9,  narrow-oblong  and  acute,  finely  serrate:  flowers  rather  large, 
rose-color.    Swamps. 

R.  virginiana,  Mill.  Usually  low,  with  stout  hooked  spines:  stipules 
rather  broad;  leaflets  about  7,  smooth  and  mostly  shining  above:  flowers 
large,  rose-color.    Moist  places. 

R.  humilis,  Marsh.  Three  feet  or  less  tall,  with  straight,  slender  spines: 
stipules  narrow;  foliage  usually  less  shining.    Dry  soils. 

R.  rubiginosa,  Linn.  Sweet  briar.  Eglantine.  Erect,  4-8  ft.,  curving, 
armed  with  stout  recurved  prickles,  with  weaker  ones  intermixed:  leaflets 
5-9,  ovate  or  oval,  coarsely  and  doubly  serrate  and  resinous  or  glandular, 
pubescent  beneath,  very  aromatic:  flowers  small,  pink  or  white,  solitary, 
single  or  double.    Naturalized  from  Europe  and  in  cultivation. 


ROSACEA  391 

9.  AMELANCHIER.    Service  Berry.    June  Berry. 

Small  trees  or  shrubs,  with  smooth,  grayish  bark:  leaves  simple,  peti- 
oled,  serrate:  flowers  white,  in  racemes,  or  rarely  solitary;  calyx-tube  5- 
cleft;  petals  5;  stamens  many,  short,  inserted  on  calyx-throat;  ovary 
inferior,  apparently  10-celled,  with  1  ovule  in  each  cavity;  styles  5,  united 
below:  fruit  a  berry-like  pome,  4-10-celled. 

A.  canadensis,  Medic.  Shadbush.  Small  tree  or  bush  5-50  ft.  high, 
with  snowy  white  flowers  in  very  early  spring  before  the  foliage:  leaves 
ovate  to  oblong,  sharply  serrate,  acute  at  apex,  base  cordate,  soon  smooth; 
stipules  long  and  silky-hairy:  fruit  red  or  purple  pomes,  on  slender  pedicels, 
6weet  and  edible.    Woods,  common. 

10.  PYRUS.   Pear.   Apple. 

Small  trees  or  shrubs  with  alternate  leaves,  and  flowers  in  clusters  in 
spring;  flowers  5-merous:  ovaries  usually  5,  immersed  in  the  torus,  the 
styles  free. 

a.  Leaves  simple:  pear  and  apple. 

P.  communis,  Linn.  Pear.  Figs.  61,  62,  65,  66,  67,  118,  119,  196,  293. 
Leaves  ovate,  firm  and  shining,  smooth,  close-toothed:  fruit  tapering  to  the 
pedicel.    Europe. 

P.  Malus,  Linn.  Apple.  Figs.  294-295.  Leaves  ovate,  soft  -  hairy  be- 
neath, serrate:  fruit  hollowed  at  the  base  when  ripe.    Europe. 

P.  coronaria,  Linn.  Wild  crab.  Bushy  tree  to  about  20  ft.,  somewhat 
thorny:  leaves  ovate-triangular  to  heart-shaped,  cut-serrate,  or  somewhat 
lobed,  soon  smoothish:  flowers  large,  strikingly  fragrant,  rose-colored,  few 
in  a  corymb  or  cluster:  pome  flattened  at  the  ends,  long-stemmed,  indented 
at  the  attachment  to  stalk,  green,  becoming  yellowish,  fragrant  but  sour. 
Open  glades,  from  New  York,  west  and  south. 

P.  ioensis,  Bailey.  Prairie  crab.  Pubescent:  leaves  oblong  or  ovate, 
notched  or  parted  along  the  sides,  the  petioles  short:  pome  globular  or 
oblong,  short-stemmed,  with  light  dots.    Mostly  west  of  Great  Lakes. 

aa.  Leaves  compound:  mountain-ashes.  (Sorbus.) 
P.  americana,  DC  American  mountain-ash.  Tree  or  large  shrub,  native 
to  mountain  woods  in  the  East,  but  sometimes  cultivated:  leaves  odd-pin- 
nately  compound,  with  13-15  leaflets  that  are  lanceolate,  taper-pointed,  ser- 
rate, bright-green  above:  flowers  numerous,  small,  white,  in  compound,  flat 
cymes;  styles  3-5:  berry-like  pomes  globose,  bright  red,  or  orange,  about  the 
size  of  peas. 

P.  Aucuparia,  Ehrh.  English  mountain-ash.  Rowan.  Leaves  pubescent 
on  both  sides  when  young,  the  leaflets  blunt:  fruit  larger  than  that  of  pre- 
ceding, about  Y2  in.  in  diameter. 

11.  CYDONIA.    Quince. 

Small  tries  or  shrubs:  flowers  and  leaves  much  as  in  Pyrus:  ovary  5- 
celled,  with  many  seeds  in  each:  fruit  a  pome,  usually  hollowed  at  top  end, 
globose,  or  pyriform. 


392  THE     KINDS    OF    PLANTS 

C.  vulgaris.  Pers.  Quince.  Six  to  15  ft.  high,  with  crooked  branches; 
flower  solitary,  large,  pale  pink  or  roseate,  on  shoots  of  the  season:  leaves 
oblong-ovate,  acute  at  apex,  with  obtuse  base,  entire.  A  small  tree  grown 
for  its  large  yellow  fruits. 

C.  japonica,  Pers.  Japan  quince.  Shrub,  3-6  ft.,  cultivated  for  hedges 
and  flowers:  branches  armed  with  short,  straight  spines:  leaves  glabrous 
and  shining,  acute  at  the  end,  serrulate,  the  stipules  conspicuously  reniform: 
flowers  in  axillary  clusters,  nearly  sessile,  crimson  or  scarlet.  Fruit  globose, 
fragrant. 

12.  CRAT^GUS.    Hawthorn.    Figs.  164-167. 

Large  bushes  or  small  trees,  much  branched,  the  wood  tough  and  hard, 
usually  very  thorny:  flowers  white  or  pink,  in  dense  umbel-like  clusters; 
petals  5,  entire;  stamens  5-10  to  many:  fruit  a  small  red  or  yellow  drupe 
containing  large  bony  stones:  leaves  simple,  mostly  toothed  or  lobed.  Many 
species  wild  in  North  America,  and  some  cultivated;  too  difficult  of  determi- 
nation for  the  beginner.  The  wild  hawthorns  are  amongst  the  most  deco- 
rative plants  in  the  American  landscape. 

13.  SPIR^A.    Spirea.    Fig.  193. 

Hardy  perennial  herbs  and  many  ornamental  shrubs:  leaves  alternate: 
flowers  white  or  roseate,  usually  small  but  many;  calyx  5-cleft,  short  and 
open;  petals  5;  stamens  many:  fruit  of  about  5  follicles,  not  inflated.  A 
large  and  very  interesting  group  of  flowering  plants,  mostly  with  white 
bloom.    Following  are  small  shrubs: 

S.  salicifdlia,  Linn.  Meadow-sweet.  Glabrous  or  nearly  so,  erect  to  3 
or  4  ft.,  stem  often  purplish:  leaves  simple,  oblong-ovate  to  lanceolate, 
serrate,  with  stipules  deciduous:  flowers  in  terminal  erect  panicles,  white 
or  pinkish-tinged,  small,  with  pods  (follicles)  5,  smooth,  many-seeded. 
Moist  or  swampy  ground.    Summer. 

S.  tomentosa,  Linn.  Hardhack.  Erect,  2-4  ft.  high,  with  pubescent 
stems,  rusty  or  hairy:  leaves  simple,  oblong  or  ovate,  serrate,  woolly  on 
lower  surface,  without  stipules:  flowers  in  terminal  thyrse-like  dense  panicles, 
pink  or  purple  (rarely  white),  the  follicles  5,  pubescent  or  woolly:  pastures 
and  low  grounds.    Late  summer. 

S.  trilobata,  Linn.  Bridal  wreath.  Large  bush  with  long  recurving 
branches  and  bearing  a  profusion  of  showy  flowers  in  flat-topped  clusters: 
leaves  round-ovate,  crenately  cut  and  3-lobed.  S.  Van  Houttei  is  an 
improved  form.  The  forms  of  this  species-group  are  the  most  popular 
cultivated  spireas. 

S.  hypericifolia,  St.  Peter's  wreath.  From  3—6  ft.,  leaves  obovate- 
oblong  or  wedge-shaped,  obscurely  toothed  or  lobed :  flowers  white,  in  many 
small  lateral  sessile  clusters,  on  short  branches.    Cultivated. 

S.  Thunbergii,  Sieb.  Compact  bush  with  very  narrow  leaves,  sharply 
serrate  and  very  light  green:  flowers  umbellate,  small,  white.  Handsome 
species  from  Japan. 


SAXIFRAGES  393 

XXX.  SAXIFRAGACE^:.  Saxifrage  Family. 
Herbs  or  shrubs  of  various  habit,  with  opposite  or  alternate  leaves 
that  usually  do  not  have  stipules:  flowers  with  ovary  mostly  inferior, 
5-mcrous,  the  stamens  usually  10  or  less  (in  a  few  eases  as  many  as 
40);  pistils  10  or  less,  either  separate  or  the  carpels  united,  tin-  fruit 
a  follicle,  capsule  or  berry.  A  polymorphous  family  comprising  some 
600  species  in  about  75  genera.  Comprises  saxifrage,  mitre-wort, 
hydrangea,  mock  orange,  currant  and  gooseberry. 

A.  Herbs. 

b.  Stamens  twice  as  many  as  petals, 
c.  Petals  entire:  stamens  usually  10. 

d.  Flowers  in   cymes  or  panicles    (rarely  solitary): 

capsule  2-beaked:  ovary  usually  2-celled 1.  Saxifraga 

DD.   Flowers     in     racemes:     ovary     1-celled:     capsule 

2-beaked.  with  1  beak  the  longer  and  larger. .  .  .2.  Tiarella 

cc.  Petals  with  edges  fringed  or  cleft 3.  Mitella 

bb.  Stamens  (fertile)  5,  or  equal  in  number  to  the  petals: 

clusters  of  sterile  stamens  opposite  each  petal 4.  Parnassia 

aa.  Shrubs. 

B.   Leaves  opposite. 
c.  Stamens  8  or  10. 

d.   Flowers  all  alike:  sepals  5 5.  Deutzia 

dd.   Flowers  usually   of   2   kinds:   the  marginal   ones 

enlarged  and  neutral,  apctalous 6.  Hydrangea 

cc.  Stamens  many:  petals  4  or  6,  large,  white 7.  Philadelphia 

bb.  Leaves  alternate 8.  Ribcs 

1.  SAXIFRAGA.    Saxifrage. 

Herbs,  with  root-leaves  in  rosette:  flowers  perfect,  small,  whitish,  in 
cymes  or  panicles,  on  leafy  stems  or  leafless  scapes;  sepals  5,  more  or  less 
united;  petals  5,  entire  inserted  on  calyx-tube;  stamens  mostly  10;  styles 
2  and  capsule  2-beaked,  or  of  nearly  separate  divergent  pods. 

S.  virginiensis,  Michx.  Little  perennial  herb  with  spatulate  or  obovate, 
petioled,  crenate,  thick  leaves:  scape  3-12  in.,  erect,  viscid-pubescent, 
bearing  many  small,  white  flowers  in  a  loose  cyme,  the  petals  exceeding  the 
calyx.    In  early  spring,  on  moist  banks  and  rocks. 

2.  TIARELLA.    False  Mitrewort. 

Perennials,  with  small  white  flowers  in  racemes:  calyx  white,  eampan- 
ulate,  5-lobed;  petals  5,  entire  on  claws;  stamens  10,  with  long  filaments 
from  the  calyx-tube;  ovary  1-celled,  nearly  superior;  styles  2,  long  and 
slender:  capsule  with  two  very  unequal  beaks. 

T.  cordifolia,  Linn.  Scape  slender,  pubescent,  leafless  or  with  1  or  2 
leaves:  stoloniferous  from  rootstocks:  leaves  cordate,  lobed  or  toothed, 
petioled,  slightly  hairy  or  downy  beneath:  flowers  white,  in  short  raceme. 
Spring.    Handsome. 


394  THE    KINDS    OF    PLANTS 

3.  MITELLA.    Mitrewort.    Bishop's  Cap. 

Delicate  little  perennials,  with  small,  white  flowers  in  a  raceme  or  spike, 
the  basal  leaves  heart-shaped  or  reniform :  scape  with  2  opposite  leaves,  or 
1  or  none:  calyx  short,  5-cleft,  adherent  to  base  of  ovary;  petals  5,  white 
edges  daintily  fringed,  inserted  on  calyx;  stamens  5-10,  with  short  fila- 
ments, on  petals;  styles  2,  short. 

M.  diphylla,  Linn.  About  1  ft.  tall:  root-leaves  in  a  cluster,  cordate, 
ovate,  somewhat  3-5-lobed,  toothed,  hairy:  scape  rather  hairy,  with  2 
opposite  nearly  sessile  leaves  near  middle:  flowers  tiny,  many,  white.  May 
to  early  June,  in  rich  woods. 

M.  nuda,  Linn.  Very  delicate  and  slender:  scape  usually  leafless:  basal 
leaves  reniform,  crenate:  flowers  few,  greenish,  very  small,  pedicelled;  not 
common.    Damp,  cold  woods,  northward.     Late  spring  and  early  summer. 

4.  PARNASSIA.   Grass  of  Parnassus. 

Low,  glabrous  perennials,  belonging  mostly  to  marshy  or  wet  situations: 
root-leaves  in  rosettes,  rounded,  entire;  stem-leaves  1  or  few,  alternate: 
flowers  solitary,  terminal,  on  a  scape-like  stem,  white  or  greenish;  calyx 
5-lobed  to  near  base;  fertile  stamens  5,  alternating  with  the  5  whitish 
petals,  a  cluster  of  sterile  filaments  at  base  of  each  petal;  ovary  superior 
1-celled,  with  4  parietal  placenta?,  and  usually  4  stigmas. 

P.  caroliniana,  Michx.  One  flower  with  sessile  petals,  white,  with  green- 
ish veins,  1-1 J^  in.  broad:  root-leaf  thickish,  ovate  or  cordate,  1  leaf  usually 
near  base  of  scape:  6-15  in.  high.    Wet  places.    Summer. 

5.  DEtTTZIA. 

Shrubs,  having  opposite,  simple,  exstipulate  leaves:  flowers  panicled  or 
racemed,  numerous,  white  or  pinkish:  calyx -lobes  5;  petals  5  to  many;  sta- 
mens 10,  5  long  and  5  short,  the  filaments  flat,  commonly  with  3  prongs, 
the  middle  prong  antheriferous;  ovary  inferior,  styles  3-5. 

D.  gracilis,  Sieb.  &  Zucc.  Grows  to  2  or  3  ft.:  flowers  many,  white,  single 
or  double:  leaves  oblong-lanceolate,  sharply  serrate,  green  and  smooth. 
June.    Cultivated  from  Japan. 

D.  scabra,  Thunb.  Tall,  pubescent:  leaves  ovate  or  oblong-ovate,  finely 
crenate  or  serrate:  flowers  pinkish.  Later-blooming  than  preceding,  and 
much  larger.    China  and  Japan. 

6.  HYDRANGEA. 

Shrubs,  with  opposite,  stalked  exstipulate  leaves,  and  flowers  of  two 
kinds  in  terminal  corymbs  or  cymes,  the  outer  ones  usually  sterile,  often 
apetalous,  consisting  merely  of  a  showy,  flat  or  spreading  5-lobed  calyx,  the 
fertile  flowers  small,  with  calyx-tube  4-5-toothed;  petals  4  or  5:  stamens  8- 
10,  filaments  slender;  ovary  inferior,  2-celled  (rarely  3-  or  4-celled) ;  styles  2-4. 

H.  arborescens,  Linn.  Leaves  ovate,  obtuse  or  cordate  at  base,  acumi- 
nate, serrate,  green  on  both  surfaces,  nearly  or  quite  smooth:  flowers  in 
flat  cymes,  often  all  fertile,  but  sometimes  with  many  large,  white,  sterile 
flowers.    Along  streams.    June  to  July. 


SAXIFRAGE    FAMILY  395 

H.  Hortensia,  DC.  Smooth,  with  large,  toothed,  bright  green  oval 
leaves  and  flowers  nearly  all  neutral,  pink,  blue  or  whitish,  in  great  round- 
ish clusters.    China  and  Japan.     Cultivated  in  greenhouses. 

H.  paniculata,  Sieb.  Somewhat  pubescent,  with  oblong-ovate,  long- 
pointed,  dull,  sharp-toothed  leaves,  and  whitish  flowers  in  great  elongated 
panicles.    Japan.    The  common  hydrangea  of  lawns. 

7.  PHILADELPHUS.    Mock  Orange  (from  the  flowers).    Syringa. 

Shrubs  with  showy  corymbose  or  paniculate  white  flowers  and  opposite 
simple  leaves:  petals  4  or  5;  stamens  20  or  more;  ovary  3-5-loculed,  becom- 
ing a  capsule. 

P.  coronarius,  Linn.  Tall  shrub  with  erect  branches:  leaves  oblong- 
ovate  and  smooth:  flowers  cream-white,  fragrant,  in  close  clusters,  in  late 
spring.    Europe. 

P.  grandiflorus,  Willd.  Tall,  with  long  recurving  branches:  leaves  ovate- 
pointed  and  somewhat  downy  beneath:  flowers  pure  white,  scentless,  in 
loose  clusters.   Virginia,  south,  and  planted. 

8.  RIBES.    Gooseberry  and  Currant. 

Low  shrubs,  often  prickly,  with  alternate  digitately  lobed  leaves: 
flowers  small;  sepals  5  and  petal-like,  on  the  ovary;  petals  and  stamens  5, 
borne  on  the  calyx:  fruit  a  small  globular  berry. 

a.  Gooseberries:  flowers  1-3:  usually  spines  below  the  leaves. 

R.  oxyacanthoides,  Linn.  Small  bush,  with  long,  graceful  branches  and 
very  short  thorns  or  none:  leaves  thin,  orbicular-ovate,  about  3-lobed, 
the  edges  thin  and  round-toothed:  flowers  on  very  short  peduncles,  the 
calyx-lobes  longer  than  the  calyx-tube,  the  ovary  and  berry  smooth,  the 
fruit  reddish  or  green.  Swamps  North;  probable  parent  of  Houghton  and 
Downing  gooseberries. 

R.  Grossularia,  Linn.  English  gooseberry.  Stiffer  and 
denser  bush,  with  firm  and  thickish  more  shining  leaves, 
which  have  revolute  margins:  ovary  downy  and  the  large 
fruit  pubescent  or  bristly.  Europe;  parent  of  the  large- 
fruited  gooseberries. 

R.  Cynosbati,  Linn.  Tall,  open  prickly  bush,  with 
thickish  bluntly  3-lobed  downy  leaves  and  long  peduncles 
bearing  3  or  more  flowers  with  calyx-lobes  shorter  than 
the  tube:  leaves  rounded  and  3-lobed:  fruit  dull  purple, 
either  prickly  or  smooth.    Common  in  dry  places.  640.  Ribes.vulgare. 

aa.  Currants:  flowers  in  long  racemes:  no  spines. 

R.  vulgare,  Lam.  Red  and  white  currant.  Fig.  540.  Erect  bush,  with 
broad-cordate  3-5-lobed  leaves  with  roundish  lobes  and  not  strong-smelling: 
racemes  drooping,  the  flowers  greenish  and  nearly  flat  open:  berries  (cur- 
rants) red  or  white.    Europe. 

R.  nigrum,  Linn.     Black  currant.    Stronger  bush,  with  strong-scented 


396 


THE     KINDS     OF     PLANTS 


leaves  and  larger  oblong  or  bell-shaped  flowers  with  bracts  much  shorter 
than  the  pedicels:  berries  black  and  strong-smelling.    Europe. 

R.  floridum,  L'Her.  (R.  americanum,  Marsh.).  Wild  black  currant. 
Fig.  541.  Straggling  bush,  with  heart-shaped  3-5-lobed  doubly  serrate  some- 
what scented  leaves:  flowers  in  long  racemes,  whitish,  with  bracts  longer 
than  the  pedicels:  fruit  black,  scented.    Woods. 

R.  aureum,  Pursh.  Golden,  buffalo,  or  flowering  currant.  Fig.  542. 
Large  bush,  with  racemes  of  long-tubular  yellow  very 
fragrant  flowers:  fruit  blackish.  Missouri,  west,  but  com- 
mon in  gardens  for  its  flowers. 


XXXI.  ONAGRACE.E.  Evening  Primrose  Family. 

Mostly  herbs:  leaves  various,  alternate  or  opposite, 
without  stipules:  flowers  perfect,  usually  4-parted,  with 
calyx-tube  joined   to  ovary  and  often  prolonged,  the 
'     13e3       margin    4-lobed,    lobes   valvate    in    the   bud,   usually 
reflexed  in  flower:  petals  4  (2-9),  on  throat  of  calyx- 
tube:   stamens  as   many  or  twice   as  many  as  petals:   style  1,  slen- 
der,   the    stigma    4-lobed     (sometimes    2-lobed);     ovary    2-4-celled. 
More  than  300  species  and  40  genera,  of  wide  distribution. 

a.   Calyx-tube  much  prolonged  beyond  the  ovary. 

b.   Lobes  generally  reflexed:  fruit  a  dry  capsule,  dehiscent.. 1.  Oenothera 
bb.  Lobes  large  and  spreading:   calyx-tube  highly  colored: 

fruit  a-4-celled  berry:  flowers  drooping 2.  Fuchsia 

aa.  Calyx-tube  not  much  prolonged. 

B.  Stamens  8;  petals  4 3.  Epilobium 

bb.   Stamens  2;  petals  2 4.  Circaa 

1.  OENOTHERA.    Evening  Primrose. 

Herbs,  stems  usually  erect:  leaves  alternate:  flowers  brightly  colored, 
regular,  axillary  or  in  terminal  spikes;  calyx-tube  prolonged  beyond  ovary, 
the  4  lobes  usually  reflexed,  sometimes  soon  falling;  petals  4; 
stamens  8;  stigma  4-lobed;  capsule  usually  narrow  and  long, 
4-celled,  many-seeded. 

(E.  biennis,  Linn.   Common  evening  primrose.  Figs.  276,  415. 
Stem  erect,    2-5    ft.,   hairy  and    leafy:    leaves    lance-oblong, 
somewhat  repandly-toothed ;  flowers  pure  yellow,  fragrant,  in 
l»r  terminal,  leafy  spikes,  not  remaining  open  in  broad  sunshine: 
calyx-tube  2  to  3  times  longer  than  ovary  and  lobes  reflexed ; 
petals  obcordate:  pod  oblong,  bluntly  4-angled.    A  very  com- 
mon  biennial   of  roadside   and   pasture,    opening   quickly  at 
542.    Ribes    nightfall, 
aureum.  (E.  fruticosa,  Linn.    Sundrops.  Biennial  or  perennial:  stem 

mONKTVOF 


ONAGRACE.E  397 

erect,  1-3  ft.,  leafy,  more  or  less  hairy:  flowers  yellow,  1-2  in.  in  diameter, 
in  corymbed  racemes,  open  in  daytime:  pod  decidedly  4-angled  and  4- 
ribbed,  rather  downy,  shortly  stalked.   Dry  soil. 

CE.  pumila,  Linn.  Resembles  preceding,  but  smaller,  5-12  inches  high: 
corolla  yellow,  about  Yi  hi.  across:  pod  smooth,  4-angled,  sessile  or  short- 
stalked.    Dry  soil. 

2.  FUCHSIA.    Figs.  172,  183,  205. 

Herbs  or  shrubby  plants  (some  trees):  leaves  opposite,  or  3  in  a  whorl: 
flowers  drooping,  axillary;  calyx-tube  colored,  extended  beyond  ovary; 
margin  4-lobed,  spreading;  petals  4  on  throat  of  calyx;  stamens  8,  project- 
ing; style  long:  fruit  a  4-celled  berry.  A  number  of  species  of  these  orna- 
mental plants  in  cultivation.    Mainly  native  to  South  America. 

F.  magellanica,  Lam.  Smooth  and  tender:  leaves  simple,  toothed, 
slender-petioled:  flowers  hanging  on  long  peduncles  from  leaf  axils;  calyx 
red,  lobes  long,  exceeding  the  tube  and  the  petals;  petals  blue  or  purple  or 
red,  obovate,  notched,  convolute  about  the  bases  of  the  long  filaments  and 
style.  The  common  window-garden  fuchsias  (F.  speciosa)  have  descended 
from  this  species,  more  or  less  hybridized  with  others. 

3.  EPILOBIUM.    Willow-herb. 

Mostly  perennials,  with  leaves  nearly  sessile,  alternate  or  opposite: 
flowers  white  or  purple,  spicate,  racemed,  or  solitary;  calyx -tube  little 
if  any  longer  than  ovary,  limb  4-cleft;  petals  4;  stamens  8;  stigma  4-lobed: 
fruit  linear,  4-sided,  dehiscent  by  4  loculicidal  valves,  many-seeded:  seeds 
with  tuft  of  long,  silky  hair  attached  to  tip. 

E.  angustifolium,  Linn.  Purple  fireweed.  Stem  simple,  erect,  4-7  ft.: 
lower  leaves  alternate,  lanceolate,  nearly  entire:  racemes  long,  terminal, 
showy ;  flowers  large,  about  1  in.  across,  reddish  purple.    Common  in  woods. 

4.  CIRCjEA.    Enchanter's  Nightshade. 

Low,  delicate,  and  insignificant  perennial  herbs,  with  creeping  root- 
stocks:  leaves  opposite,  very  thin,  petioled:  flowers  very  small,  in  terminal 
and  lateral  racemes;  calyx-tube  slightly  prolonged  beyond  ovary;  parts  of 
the  flower  in  2's.    Damp,  shady  places.    Summer. 

C.  Lutetiana,  Linn.  Stem  erect,  1-2  ft.  tall,  pubescent:  leaves  ovate, 
slightly  repand-toothed:  flowers  white  or  pink,  about  Kin.  in  diameter,  on 
slender  pedicels,  bractless:  fruit  small,  round,  2-celled,  bristly.  The  com- 
mon species  in  damp,  shady  places  in  summer. 


XXXII.  UMBELLfFEILE.   Parsley  Family. 

Herbs,  mostly  strong-scented  and  with  compound  alternate  leaves 
"with  petioles  expanded  or  sheathing  at  the  base:  flowers  small,  mostly 
perfect)  5-merous,  epigynous,  in  umbels  or  umbel-like  clusters;  stamens 
5:  fruit    consisting    of   2  carpels,  which   are   dry  and    seed-like    and 


398  THE     KINDS    OF    PLANTS 

indehiscent.  Oil-tubes,  in  the  form  of  stripes,  1  or  several  in  the 
intervals  of  the  ribs  on  the  fruits,  also  sometimes  under  the  ribs  and 
on  both  faces  of  the  fruit,  are  characteristic  features  of  the  Umbel- 
liferae.  A  well-marked  natural  family  of  about  1,500  species  in  about 
160  genera.  Some  of  the  species  are  poisonous.  Here  belong  parsley, 
parsnip,  carrot,  celery,  caraway,  sweet  cicely.  Rather  difficult  for 
the  beginner. 

a.  Fruits  bristly 1.  Daucus 

aa.  Fruits  not  bristly. 
b.  The  fruits  winged. 

c.  Wing    single,     surrounding    the    margin:    flowers 

yellow 2.  Pastinaca 

cc.  Wing  double  on  margin:  flowers  white 3.  Angelica 

bb.  The  fruits  wingless. 

C.  Fruit  long  and  slender,  tapering  at  base:  no  appar- 
ent oil-tubes:  flowers  white 4.  Osmnrrhiza 

cc.  Fruit  ovate  or  orbicular. 

D.  Plant  low  and  delicate:  blooms  in  earliest  spring: 

stem  with  1  or  2  leaves,  if  any 5.  Erigenia 

dd.   Plant  tall:  stems  leafy. 

E.  Axis    not    splitting    in  two  when  the  carpels 

fall  from  it 6.  Apium 

ee.  Axis  splitting  in  two  when  the  carpels  or  '  'seeds' ' 

fall.    Leaf-segments  filiform,  flowers  white..  .7.  Carum 

1.  DAfrCUS.    Carrot. 

Annuals  or  biennials,  bristly,  slender  and  branching,  with  small  white 
flowers  in  compound  umbels,  the  rays  of  which  become  inflexed  in  fruit:  the 
fruit  oblong,  ribbed  and  bristly. 

D.  Carota,  Linn.  Carrot.  Figs.  194,  410.  Leaves  pinnately  decompound, 
the  ultimate  segments  lanceolate:  outer  flowers  with  larger  petals.  Europe; 
cultivated  for  the  root,  and  extensively  run  wild. 

2.  PASTINACA.    Parsnip. 

Tall,  smooth  biennials  of  strict  habit  and  with  pinnately  compound 
leaves:  flowers  yellow,  in  compound  umbels  with  scarcely  any  involucres: 
fruit  oval,  very  thin,  wing-margined. 

P.  sativa,  Linn.  Parsnip.  Flowering  stem  2-4  ft.  tall,  grooved,  hol- 
low: leaflets  ovate  or  oblong,  sharp-toothed.  Europe;  cultivated  for  its 
roots  and  also  run  wild. 

3.  ANGELICA. 

Strong,  tall,  perennial  weeds,  with  great  compound  leaves  and  large 
umbels  of  small  white  flowers,  with  involucre  and  involucels  none,  or  only  a 
few  small  bracts:  fruit  ovate  or  oval,  flattened,  with  rather  broad,  marginal 
wings:  oil-tubes  many. 


UMBELLIFERiE  399 

A.  atropurpurea,  Linn.  A  groat  weed,  3-8  ft.  tall,  in  moist,  rich  soil  or 
swampy  ground,  with  stem  stout,  smooth,  strong-scented,  often  purple: 
leaves  large,  3-compound,  on  petioles  with  broad,  inflated  bases:  umbels 
large,  flowers  greenish  white. 

4.  OSMORRHIZA.   Sweet  Cicely. 

Herbs,  1-2  ft.  or  more,  perennial,  glabrous  or  pubescent,  from  thick- 
clustered,  aromatic  roots:  leaves  2  or  3  times  pinnately  compound; 
leaflets  variously  toothed, — the  whole  leaf  fern-like:  flowers  many,  small, 
white,  in  compound,  rayed  umbels:  fruit  linear  to  linear-oblong,  attenuate 
at  base,  short-beaked,  compressed,  with  5  bristly  ribs:  no  oil-tubes. 

O.  Claytdnii,  Clarke.  Stout,  downy,  1-2  or  3  ft.:  style  conical,  shorter 
than  the  ovary. 

O.  longistylis,  DC.  Glabrous  or  nearly  so,  otherwise  much  like  the  pre- 
ceding: style  slender  and  about  as  long  as  the  ovary:  root  aromatic. 

5.  ERIGENiA. 

Little,  glabrous  perennial,  early  flowering:  simple  stem,  springing  from 
a  rounded  tuber:  leaves  finely  compound:  flowers  in  small  clusters,  in 
leafy  bracted  umbels,  small,  white;  calyx-teeth  wanting;  petals  obovate  or 
spatulate:  fruit  nearly  orbicular,  compressed  on  sides,  glabrous,  notched 
at  both  ends. 

E.  bulbosa,  Nutt.  Harbinger  of  spring.  A  delicate  and  pretty  but  incon- 
spicuous plant,  4-10  in.  high,  springing  from  the  ground  in  earliest 
spring,  on  sunny  slopes  of  woodlands.  The  little  white  petals  and  brown  or 
purplish  anthers  give  a  "pepper-and-salt"  appearance. 

6.  APIUM.    Celery. 

Annuals  or  biennials,  with  large  pinnate  leaves:  flowers  white,  in  small 
umbels:  fruit  small,  usually  as  broad  as  long,  each  carpel  5-ribbed:  axis, 
from  which  the  carpels  fall,  not  splitting  in  two. 

A.  graveolens,  Linn.  Celery.  Biennial,  smooth:  leaflets  3-7,  wedge- 
shaped  or  obovate,  the  lower  ones  about  3-divided,  round-toothed,  Europe: 
cultivated  for  its  petioles,  which  have  become  greatly  enlarged.  Many 
cultivated  forms. 

7.  CARUM.    Caraway. 

Slender  and  erect,  smooth  annual  and  biennial  herbs  with  pinnate 
leaves:  flowers  white,  in  compound  umbels  provided  with  involucres:  axis 
bearing  the  carpels,  splitting  in  two  at  maturity. 

C.  Carui,  Linn.  Caraway.  Stem  furrowed,  1-2  ft.:  leaves  cut  into 
thread-like  divisions:  flowers  white.  Europe.  Cultivated  for  its  fruits, 
known  as  "Caraway  seed,"  and  also  run  wild. 

C.  hortense,  Hoffm.  (C.  Petroselinum,  Benth.  Petroselinum  hortense, 
Hoffm.).  Parsley.  One  to  3  ft. :  leaflets  ovate  and  3-cleft,  often  much  cut  or 
"curled"  in  the  garden  kinds:  flowers  yellowish.  Europe.  Grown  for  its 
foliage,  used  for  garnishing  and  flavoring. 


400  THE    KINDS    OF    PLANTS 

CC.   GAMOPETALM. 

XXXIII.  LABIATE.   Mint  Family. 

Herbs,  usually  of  aromatic  scent,  with  4-cornered  stems  and  oppo- 
site usually  simple  leaves:  flowers  typically  2-lipped;  stamens  4 
in  2  pairs,  or  only  2;  ovary  deeply  4-lobed,  forming  4  indehiscent 
nutlets  in  fruit.  A  well-marked  family  of  some  2,700  species,  dis- 
tributed in  about  150  genera,  of  both  temperate  and  tropical  regions. 
To  this  family  belongs  the  various  mints,  as  peppermint,  spearmint, 
catnip,  hyssop,  thyme,  pennyroyal,  savory,  rosemary,  sage,  hore- 
hound,  balm,  basil.  Flowers  mostly  in  whorls  in  the  axils  of  leaves  or 
bracts,  sometimes  forming  interrupted  spikes. 

a.  Stamens  2. 

b.  Calyx  nearly  equally  toothed. 

c.  Lobes  5:  throat  hairy 1.  Monarda 

cc.  Lobes  4-5:  throat  naked 2.  Lycopus 

bb.  Calyx  2-lipped. 

c.  Throat  naked  within 3.  Salvia 

cc.  Throat  hairy:  plants  very  pungent-scented 4.  Hedeoma 

aa.  Stamens  4. 

b.   Corolla  scarcely  2-lipped:  lobes  nearly  equal. 

c.  Border  of  corolla  44obed:  upper  lobe  broadest  and 

emarginate 5.  Mentha 

cc.  Border  of  corolla  4-lobed,  with  a  deep  fissure  be- 
tween the  2  upper  lobes 6.  Teucrium 

bb.  Corolla  strongly  2-lipped. 
c.  Calyx  2-lipped. 

d.  Lips  of  calyx  toothed:  flowers  in  dense  terminal 

spikes  or  heads 7.  Prunella 

dd.  Lips    of    calyx    entire,    the    upper    humped,    or 
appendaged:   flowers   axillary  in   bracts  or  leaf 

axils,  solitary  or  racemed 8.  Scutellaria 

cc.  Calyx  nearly  or  quite  regular. 

D.  Upper  pair  of  the  stamens  the  longer 9.  Nepeta 

dd.   Upper  pair  of  the  stamens  the  shorter. 

E.  Stamens'  short,    included    in    the   tube   of   the 

corolla 10.  Marrubium 

ee.  Stamens  long,  projecting  from  the  corolla-tube.  11.  Leonurus 

1.  MONARDA.   Horse-mint. 

Rather  stout,  mostly  perennials,  with  flowers  in  close  terminal  heads: 
calyx  tubular,  15-nerved,  hairy  in  the  throat,  the  teeth  nearly  equal:  corolla 
strongly  2-lipped,  the  upper  lip  erect,  the  lower  spreading  and  3-lobed. 

M.  fistulosa,  Linn.     Two  to  5  ft.,  in  clumps:  leaves  ovate-lanceolate: 


THE    MINT    FAMILY  401 

flowers  in  a  clover-like  flattish  head:  calyx  slightly  curved:  corolla  about 

1  in.  long,  purple.    Common  in  dry  places. 

M.  didyma,  Linn.  Oswego  tea.  Bee  balm.  Stem  4-angled  and  branch- 
ing: leaves  petioled,  shortly  ovate  to  lanceolate,  those  about  the  terminal 
head  tinged  with  red:  not  very  common  wild,  but  cultivated. 

2.  LYCOPUS.    Water  Hoarhound. 

Low  perennials,  with  stolons  or  suckers,  much  like  the  mints  (Mentha) 
and  growing  in  similar  moist  or  shady  places:  not  aromatic:  flowers  small, 
white  clustered  in  leaf  axils:  calyx  bell-shaped,  4-  to  5-toothed:  corolla 
campanulate,  with  4  nearly  equal  lobes:  fertile  stamens  2,  the  other  2  rudi- 
mentary or  wanting:  flowers  small,  white  or  purplish,  bracted  and  whorled 
in  axillary  clusters. 

L.  virginicus,  Linn.  Stem  6  in.  to  2  ft.,  obtusely  4-angled,  green  or 
often  purplish:  stoloniferous:  leaves  oblong  or  ovate-lanceolate,  serrate, 
except  at  base,  short-petioled  or  nearly  sessile.    In  moist  places.    Summer 

3.  SALVIA.    Sage. 

Annuals  or  perennials,  mostly  with  large  and  showy  flowers:  calyx  and 
corolla  2-lipped:  upper  lip  of  corolla  large  and  usually  arched,  entire  or 
nearly  so,  the  lower  lip  spreading  and  3-lobed:  stamens  2,  short,  the  anther 
locules  separated  by  a  transverse  bar. 

S.  officinalis,  Linn.  Common  sage.  Erect  low  perennial,  with  gray 
pubescent  foliage:  leaves  oblong-lanceolate,  crenulate,  very  veiny:  flowers 
blue,  in  spiked  whorls.    Europe;  used  for  seasoning. 

S.  splendens,  Sell.  (S.  cocclnea  of  gardens).  Scarlet  sage.  Tender  peren- 
nial from  Brazil,  but  much  cultivated  for  its  bright  scarlet  floral  leaves, 
calyx,  and  corolla:  leaves  ovate-pointed. 

4.  HEDEOMA.    Mock  Pennyroyal. 

Low,  aromatic-fragrant  herbs,  with  small  bluish  flowers  in  loose  axillary 
clusters,  often  forming  terminal  racemes  or  spikes:  calyx  tubular,  13-nerved, 
swollen  on  lower  side,  hairy  in  throat,  2-lipped;  corolla  2-lipped,  upper  lip 
erect,  flat,  emarginate,  the  lower  spreading  and  3-cleft,  2  perfect  stamens; 

2  shorter  sterile  stamens  sometimes  present. 

H.  pulegioides,  Pers.  Small  animals  of  pungent  fragrance  and  taste, 
with  slender  stem  (i  12  in.  tall,  erect,  branching,  pubescent:  leaves  ovate 
to  oblong,  about  1  in.  long,  few-toothed,  petiolate:  whorls  few-flowered,  the 
corolla  bluish,  pubescent.   In  dry  fields  and  woods.  Summer. 

5.  MENTHA.    Mint. 

Low  perennials:  calyx  with  5  similar  teeth:  corolla  nearly  or  quite  regu- 
lar, 4-cleft:  stamens  4,  equal:  flowers  in  heads  or  interrupted  spikes,  pur- 
plish  or  white. 

M.  piperita,  Linn.  Peppermint.  Straggling,  1-3  ft.  tall,  the  plant  dark 
colored  (stems  purplish):  leaves  ovate,  oblong,  or  narrower,  acute,  sharply 
serrate:  flowers  light  purple,  in  thick  spikes  1-3  in.  long.    Europe. 


402 


THE     KINDS     OF     PLANTS 


M.  spicata,  Linn.  (M.  vlridis,  Linn.).  Spearmint.  Fig.  543.  Erect  and 
smooth,  1-2  ft.,  green:  leaves  lanceolate  and  sharply  serrate:  flowers  whitish 
or  tinted,  in  long,  interrupted  spikes.  Europe.  Along  roadsides,  and 
cultivated. 

M.  canadensis,  Linn.  Wild  mint.  One  to  2  ft.,  pubescent:  leaves  lanceo- 
late: flowers  tinted,  in  whorls  in  the  axils  of  the  leaves.    Low  grounds. 

6.  TEUCRIUM.    Germander. 

Perennial  herbs  (or  shrubs)  with  small,  pinkish,  rather  irregular  flowers, 
in  terminal  bracted  spikes  (or  heads)  or  verticillate  in  the  upper  axils  of  the 
stem-leaves:  calyx  5-toothed,  10-nerved:  corolla  5-lobed,  with  4  upper  lobes 
oblong,  somewhat  equal,  and  turned  forward,  the  lowest  lobe  large,  rounded: 
stamens  4,  in  2  pairs,  projecting  from  a  deep  fissure  between  the  2  upper 
lobes  of  the  corolla. 

T.  canadense,  Linn.  Erect,  pubescent,  1-3  ft.:  leaves 
ovate-lanceolate,  irregularly  serrate,  short-petioled:  bracts 
under  the  flowers  linear-lanceolate,  about  as  long  as  calyx: 
spike  long  and  slender,  the  few  odd-looking  purplish  or 
pinkish  flowers  in  crowded  verticels.  Damp  ground.  Late 
summer. 

7.  PRUNELLA.   Self-heal. 

Low,  usually  unbranched  perennials  without  aromatic 
odor:  calyx  about  10-nerved,  2-lipped:  corolla  2-lipped,  the 
upper  lip  arched  and  entire,  the  lower  one  3-lobed:  sta- 
mens 4,  in  pairs,  ascending  under  the  upper  lip. 

P.  vulgaris,  Linn.  Self-heal.  Three  to  10  in.  tall,  with 
ovate  or  oblong,  usually  slightly  toothed  leaves:  flowers 
small,  violet  (rarely  white),  in  a  dense,  oblong,  clover-like 
head  or  spike.  Common  in  grassy  places;  often  a  weed  in 
lawns. 

543.  8.  SCUTELLARIA.    Skullcap. 

Mentha  spicata.  .  . 

Perennials,  bitter,  not  aromatic:  flowers  solitary  or  in 

pairs,  axillary  or  in  bracted  spike-like  racemes;  calyx  bell-shaped,  2-lipped, 
the  lips  closed  in  fruit,  the  upper  one  appendaged  on  the  back  (at  maturity 
the  calyx  splits  to  the  bottom,  the  upper  lip  usually  falling  off);  corolla- 
tube  elongated,  curved  and  ascending,  swollen  above  the  throat,  2-lipped, 
the  upper  lip  arched  and  notched:  stamens  4,  ascending  in  pairs  under 
the  upper  lip,  the  upper  pair  shorter. 

S.  laterifolia,  Linn.  Mad-dog  skullcap.  Smooth,  1-2  ft.  high:  stem 
nearly  or  quite  erect,  much  branched,  slender,  leafy:  leaves  thin,  ovate- 
lanceolate,  pointed,  serrate,  petioled:  flowers  blue  (rarely  white),  small, 
J£~H  in.  long,  in  axillary,  1-sided  racemes  (some  terminal).  Wet,  shaded 
places.  Summer.  Several  related  species  grow  in  bogs  and  along  slow 
streams,  but  most  of  them  will  not  be  likely  to  attract  the  attention  of  the 
beginner,  although  all  are  odd  or  interesting. 


MINT   AND    VERVAIN    FAMILIES  403 

9.  NEPETA.    Catmint. 

Perennials,  mostly  sweet-scented :  calyx  nearly  equally  5-toothed ;  corolla 
2-lippod,  the  upper  lip  erect  and  somewhat  concave,  the  lower  3-lobed: 
stamens  4,  in  pairs  under  the  upper  lip,  the  outer  pair  the  shorter. 

N.  Cataria,  Linn.  Common  catmint  or  catnip.  Figs.  213,  414.  Erect, 
2-3  ft.,  pubescent:  leaves  cordate-ovate,  crenate,  grayish:  corolla  tinted: 
flowers  in  interrupted  spikes.    Introduced  from  Europe. 

N.  hederacea,  Trev.  (N.  Glechoma,  Benth.).  Ground  ivy.  Gill-over-the- 
ground.  A  weed  from  Europe,  but  familiar  almost  everywhere:  creeping, 
with  rounded,  crcnately  margined,  petioled  leaves:  flowers  bluish  purple, 
small. 

10.  MARRUBIUM.    Horehound. 

Erect  perennials,  with  white- woolly  aspect:  calyx  nearly  equally  5-10- 
toothed,  the  teeth  very  sharp:  corolla  2-lipped,  the  upper  lip  erect  and 
notched,  the  lower  one  spreading  and  3-lobed:  stamens  4,  included  in  the 
corolla-tube.  There  are  a  number  of  Old  World  species,  but  only  the 
following  seems  to  have  run  wild  in  this  country:. 

M.  vulgare,  Linn.  Common  horehound.  Leaves  broad-ovate  and 
crenate:  flowers  small,  white,  in  dense  whorls.    Europe,  but  common. 

11.  LEONURUS.    Motherwort. 

Erect  perennials  with  green  aspect:  calyx  about  equally  5-toothed,  the 
teeth  becoming  spine-like;  corolla  2-lipped,  the  upper  lip  somewhat  arched 
and  entire,  the  lower  spreading  and  3-lobed:  stamens  4,  ascending  under  the 
upper  lip:  nutlets  3-angled. 

L.  Cardiaca,  Linn.  Common  motherwort.  Tall:  leaves  rounded  and 
lobed:  corolla  purple,  the  upper  lip  bearded;  flowers  in  axillary  whorls. 
Introduced  from  Europe.  Common.  Other  introduced  species  may  now  and 
then  be  found. 


XXXIV.  VERBENACE.E.   Vervain  Family. 

Herbs,  shrubs  or  trees:  leaves  opposite  or  whorled  (in  our  spe- 
cies), exstipulate:  flowers  monopetalous,  often  irregular,  in  bracted 
cymes  or  panicles;  calyx  free  trom  the  ovary,  4-5-cleft;  corolla  some- 
times regular,  buc  often  more  or  less  2-lipped:  stamens  4  (rarely 
2),  in  unequal  pairs,  inserted  on  corolla,  alternate  with  lobes;  style 
1;  ovary  mostly  2-  to  4-celled  (not  lobed),  with  style  from  summit: 
fruit  dry  or  drupe-like.    About  1,200  species,  mostly  tropical. 

VERBENA.    Vervain. 

Herbs  with  simple,  opposite,  serrate  or  pinnately-lobed  leaves:  flowers 
usually  sessile,  bracted,  in  terminal  spikes:  corolla  salver-  pr  funnel-foriu; 
with  border  somewhat  unevenly  5-cjeft, 


404  THE    KINDS    OF    PLANTS 

V.  urticaefdlia,  Linn.  Perennial,  common  coarse  weed  in  waste  ground: 
4-6  ft.  tall:  leaves  oval,  coarsely  serrate,  stalked:  flowers  minute,  white,  in 
slender  spikes. 

V.  angustifdlia,  Michx.  A  perennial,  roughish  weed,  with  stems  6  in. 
to  2  ft.,  mostly  simple,  leafy:  leaves  sessile,  narrow-lanceolate,  tapering  to 
sessile  base:  flowers  small,  in  spikes;  corolla  purple:  fruits  overlapping  on 
spike.    Dry  fields. 

V.  stricta,  Vent.  Perennial,  hoary-hairy:  stem  1-3  ft.,  very  leafy:  leaves 
obovate  or  oblong,  serrate  and  nearly  sessile:  spikes  thick  and  densely 
flowered;  flowers  blue-purple,  rather  larger  than  in  other  common  Ver- 
vains, XA  in.  across,  but  few  open  at  one  time.    Westward. 

V.  hastata,  Linn.  A  common,  rather  pubescent  weed  of  the  waysides: 
stem  2-6  ft.  tall,  branching,  with  many  slender  spikes  of  the  small,  bracted, 
blue-purple  flowers,  few  flowers  in  bloom  at  one  time:  leaves  lanceolate, 
acuminate,  petioled. 

V.  canadensis,  Brit.  One  of  the  species  from  which  the  garden  Ver- 
benas have  come:  stems  rather  prostrate  and  creeping:  flowers  in  a  corymb 
or  peduncled  spike  and  showy,  of  various  colors  and  considerable  size:  leaves 
on  petioles,  ovate  in  outline,  but  pinnately  cut  or  3-parted.  Wild  from 
Indiana  west. 


XXXV.  SCROPHULARIACEjE.   Figwort  Family. 

Herbs  (trees  in  warm  countries),  of  various  habit:  flowers  perfect, 
irregular,  usually  imperfectly  5-merous:  corolla  usually  2-lipped  and 
personate:  stamens  4  in  2  pairs,  inseried  on  the  corolla,  with  some- 
times a  rudiment  of  a  fifth:  ovary  single,  2-loculed,  ripening  into  a 
several-  or  many-seeded  capsule.  About  160  genera  and  2,000  species. 
Representative  plants  are  figwort,  snapdragon,  toad-flax,  foxglove, 
mullein,  pentstemon,  monkey-flower  or  musk-plant. 

a.  Corolla  very  shallow  and  nearly  regular 1.  Verbascum 

aa.  Corolla  very  irregular,  often  personate. 

b.  Flowers  with  long  spur 2.  Linaria 

bb.  Flower  spurless,  but  saccate  or  swollen  at  the  base. .   3.  Antirrhinum 
bbb.  Flowers  not  spurred,  saccate,  or  much  swollen. 

c.  Stamens  5,  but  the  fifth  sterile,  often  a  scale  only. 
d.  Sterile  filament  a  little  scale  on  the  upper  side 

of  the  corolla:  flowers  small  and  dull-colored...    4.  Scrophularia 
dd.  Sterile  filament  elongated:  corolla  2-lipped. 

E.  Filament  shorter  than  the  others:  the  2  lips 
of    the    corolla    but    slightly    open:    seeds 

winged 5.  Chelone 

ee.  Filament  about  the  same  length  as  the  others: 

corolla  lip  open:  seeds  wingless 6.  Pentstemon 


SCKOPHULARIACE^E 


405 


ddd.  Sterile  filament,  not  conspicuous:  corolla  almost 
2-parted,    the    middle    lobe    of    the    lower    lip 

keeled,  inclosing  the  4  stamens 7.  Collinsia 

cc.  Stamens  plainly  4. 

d.  Corolla    2-lipped:    calyx    5-angled:    flowers   not 

drooping 8.  Mirmdus 

dd.  Corolla      slightly    2-lipped,     irregularly    5-lobed 

flowers  drooping 9.  Digitalis 

ddd.  Corolla  with  upper  lip  narrow  and  erect,  much 
longer  than  the  lower,  and  keeled:  anther- 
sacs   are   not   alike:   floral   leaves   colored   like 

petals 10.  Castilleja 

ccc.  Stamens  2  (or  2  others  rudimentary  or  wanting). 

d.  Corolla  2-lipped 11.  Gratiola 

dd.  Corolla  rotate,  lobes  unequal 12.  Veronica 

1.  VERBASCUM.    Mullein. 

Tall  biennials,  with  alternate  decurrent  leaves:  calyx 
and  corolla  5-parted,  the  latter  shallow  and  nearly  or  quite 
SS^i  *H*»j>       rotate ;  stamens  5,  some  or  all  of  the  filaments  woolly. 

V.  Thapsus,  Linn.  Common  mullein.  Fig.  147.  Two 
to  5  ft.,  stout  and  usually  unbranched,  white- woolly :  leaves 
oblong  and  acute  felt-like:  flowers  yellow  in  a  very  dense 
spike.    Weed  from  Europe. 

V.  Blattaria,  Linn.  Moth  mullein.    Slender  and  branch- 
Linaria  vulgaris.      inK>  green  and  nearly  smooth:  leaves  oblong,  serrate,  often 
laterally    lobed,   somewhat    clasping:    flowers    yellow    or 
cream-colored,  in  a  loose  raceme.   Weed  from  Europe. 

2.  LINARIA.    Toad-flax. 

Low  herbs,  of  various  habit:  corolla  personate,  the  throat  nearly  or 
entirely  closed,  spurred  from  the  lower  side:  stamens  4:  capsule  opening 
by  apical  pores. 

L.  vulgaris,  Mill.  Toad-flax.  Butter-and-eggs.  Figs. 
227,  281,  544.  Common  perennial  weed  (from  Europe),  1- 
2  ft.,  with  linear  leaves  and  yellow  flowers  in  racemes. 

L.  Cymbalaria,  Mill.   KenHworth  ivy.    Fig.  545.   Trail- 
ing: leaves  orbicular,  5-7-lobed:    flowers  solitary  on  long 
peduncles,  lilac-blue.    Europe;  very  common  in 
greenhouses  and  sometimes  runs  wild. 

L.  canadensis,  Dumont.  Common  annual 
or  biennial  in  dry  or  sandy  soil:  flowering  sterna 
slender  and  erect,  generally  simple  and  few- 
leaved:  also  prostrate  shoots,  more  leafy:  leaves 
narrow,  flat,  entire,  sessile,  opposite  or  whorled: 
flowers  small,  blue,  in  a  terminal,  loose,  slender 
raceme.  545.   Linaria  Cymbalaria. 


406  THE    KINDS    OF    PLANTS 

3.  ANTIRRHINUM.   Snapdbagon. 

From  Linaria  differs  chiefly  in  having  no  spur,  but  only  a  swelling  at  the 
base  of  the  corolla. 

A.  majus,  Linn.  Snapdragon.  Fig.  243.  Erect  biennial  or  perennial: 
leaves  oblong,  smooth,  entire:  flowers  erect  or  ascending,  2  in.  long,  purple 
or  white,  in  a  raceme  with  downy  axis.    Europe. 

4.  SCROPHULARIA.    Figwort. 

Herbs  perennial,  rank  and  generally  ill-smelling,  with  opposite  leaves, 
and  very  odd-looking  small,  greenish-purple  flowers,  in  simple  or  compound 
loose  terminal  cymes:  calyx  deeply  5-parted:  corolla  irregular,  with  a  globu- 
lar tube,  the  limb  5-lobed,  4  upper  lobes  erect,  but  the  lower  one  hori- 
zontal or  reflexed:  stamens  5,  4  fertile,  in  two  pairs,  the  fifth  sterile  and  a 
mere  rudiment  at  the  top  of  the  corolla-tube. 

S.  marilandica,  Gray.  Smooth,  3-6  ft.,  much  branching,  in  thickets  and 
damp  woods,  blooming  in  late  summer  and  early  fall;  stems  4-angled:  leaves 
ovate,  oblong  or  lanceolate,  coarsely  toothed,  3-9  in.  long,  on  slender  petioles : 
flowers  small,  dull-colored. 

5.  CHELONE.    Turtlehead.    Snakehead. 

Smooth,  erect  perennials,  with  opposite,  serrate  and  stalked  leaves: 
flowers  large,  sessile,  white  or  rose-tinged,  of  curious  shape,  in  the  upper 
leaf  axils,  forming  a  terminal  spike:  calyx  5-parted,  segments  acute, 
bracted  at  base:  corolla  irregular,  with  inflated  and  elongated  tube  con- 
cave underneath,  the  limb  2-lipped,  but  lips  only  slightly  open,  the  upper 
lip  broad,  usually  emarginate,  lower  lip  3-lobed,  bearded  within:  stamens  5, 
the  fifth  sterile  and  smaller,  the  filaments  woolly. 

C.  glabra,  Linn.  Two  to  4  ft.  high,  in  swamps  and  by  brooks  or  in 
wet  places.   Late  summer. 

6.  PENTSTEMON.    Beard-tongue. 

Perennial  herbs,  with  opposite  leaves,  the  upper  sessile  or  clasping: 
flowers  showy:  calyx  5-parted:  corolla  irregular,  with  tube  more  or  less 
inflated  and  2-lipped,  the  lower  lip  3-lobed:  stamens  5,  4  in  2  pairs  each 
bearing  an  anther,  the  fifth  filament  conspicuous  but  sterile,  sometimes 
longer  than  the  others  and  bearded:  fruit  a  globose  capsule  with  many  wing- 
less seeds. 

P.  hirsiitus,  Willd.  (P.  pubesccns,  Ait.).  Stems  hairy,  rather  viscid  above, 
1-2  ft.:  leaves  narrow-oblong  to  lanceolate,  minutely  toothed  or  entire; 
panicle  open:  corolla  about  1  in.  long,  2-lipped,  with  a  bearded  palate  in 
the  throat,  dull  bluish  violet  or  purplish.    Dry  situations.   May  to  July. 

7.  COLLINSIA.   Innocence.   Blue-eyed  Mart. 

Pretty  little  annuals  or  biennials,  branching  and  diffuse  with  opposite 
or  verticillate  leaves,  and  irregular  flowers,  blue  and  white,  on  pedicels, 
whorled  or  solitary  in  the  axils  of  the  upper  leaves:  corolla  2-lipped  with 
the  upper  lip  2-cleft,  the  lower  lip  3-cleft,  with  the  middle  lobe  keeled  and 


SCROPHULARIACEiE  407 

saccate,  inclosing  the  4  stamens  and  the  style:  a  fifth  stamen  reduced  to  a 
more  rudiment. 

C.  verna,  Nutt.  Stem  8-16  in.,  branching:  leaves  small,  various,  the  lower 
ovate,  the  upper  more  lanceolate  and  clasping,  margins  crenate  or  toothed: 
flowers  on  long  peduncles,  in  whorls  of  4-6:  corolla  %-%  in.,  twice  longer 
than  calyx:  3  lower  petals  sky-blue  or  pink,  upper  2  petals,  white.  An 
extremely  attractive  plant  in  woods,  blooming  April  to  June. 

s.   MIMULUS.    Monkey-flower. 

Small  herbs  with  opposite  leaves,  with  usually  showy  solitary  flowers  on 
axillary  peduncles:  calyx  5-angled  and  5-toothcd:  corolla  tubular,  the  2- 
lobed  upper  lip  erect  or  spreading;  stamens  4;  stigma  2-lobed. 

M.  ringens,  Linn.  Wild  monkey-flower.  Erect  perennial,  with  square 
stem  and  oblong  or  lanceolate  clasping  serrate  leaves:  flowers  blue  or  light 
purple,  somewhat  personate.    Wet  places. 

M.  luteus,  Linn.  Monkey-flower.  Tiger-flower. 
Fig.  540.  Annual,  with  ovate  serrate  leaves:  flowers 
large,  yellow,  blotched  with  brick-red  or  brown. 
Western  America,  and  commonly  cultivated.  To 
gardeners  often  known  as  M.  tigridioldes. 

9.  DIGITALIS.    Foxglove. 

Stem  simple  and  strict:  leaves  alternate:  flowers 
with  a  long  expanding  tube  and  a  very  short  in- 
distinctly lobed  limb,  the  throat  wholly  open: 
stamens  4. 

D.  purpurea,  Linn.  Common  foxglove.  Usually 
biennial,  tall  and  stout  (2-4  ft.):  leaves  oblong, 
nearly  or  quite  entire,  rough  and  downy:  flowers  many,  drooping,  in  a 
long,  erect  raceme,  2  in.  long,  white  to  purple  and  spotted  inside.  Old 
garden  plant  from  Europe. 

10.  CASTILLEJA.    Painted  Cup. 

Herbs,  at  least  partially  parasitic  on  roots  of  other  plants:  flowers  ses- 
sile in  leafy,  often  brilliantly  colored,  bracts;  calyx  tubular,  2-4-cleft;  corolla 
very  irregular,  tubular,  the  tube  included  in  the  calyx,  the  upper  lip  very 
long,  arched  and  keeled,  enfolding  2  pairs  of  stamens;  lower  lip  short, 
3-lobed.    Late  spring  and  summer.    Four  or  5  species  in  our  territory. 

C.  coccinea,  Spreng.  Annual  or  biennial,  8-12  in.,  with  very  striking 
inflorescence  of  scarlet  or  yellow  3-cleft  bracts  surrounding  the  flowers. 
Damp  meadows  or  thickets,  not  common  but  conspicuous. 

11.  GRATtOLA.   Hedge  Hyssop. 

Low,  mostly  perennial  herbs,  found  in  damp  situations:  leaves  opposite: 
peduncles  axillary,  1-flowered  each;  calyx  5-parted,  segments  scarcely 
equal;  corolla  2-lipped,  upper  lip  emarginate  or  2-cleft,  lower  3-lobed: 
fertile  stamens  2. 


546.  Mimulua  luteus. 


408  THE    KINDS    OF    PLANTS 

G.  virginiana,  Linn.  Stems  branching,  or  creeping  at  base,  more  or 
less  viscid,  4-6  in.  tall:  leaves  oblong  or  lanceolate,  few-toothed,  sessile: 
flowers  with  yellowish  corolla,  J£— J^  in.  long:  sterile  filaments  not  present. 
Wet  places.   All  summer. 

12.  VER6NICA.    Speedwell. 

Ours  herbs  with  leaves  mostly  opposite  or  whorled,  blue  or  white  flowers 
solitary  or  in  racemes  from  the  leaf-axils,  or  terminal;  corolla  wheel-shaped, 
the  border  irregularly  4-lobed;  stamens  2,  inserted  on  corolla-tube,  with 
slender  long  filaments:  ovary  2-celled,  style  slender:  capsule  flattened, 
notched  at  apex,  2-celled,  few-  to  numerous-seeded. 

V.  americana,  Schw.  Perennial,  weak  and  decumbent  at  base,  rooting 
at  nodes,  finally  erect:  leaves  opposite  at  base,  mostly  petioled,  thickish. 
oblong  to  lance-ovate,  serrate  racemes  axillary,  opposite,  2-3  in.  long:  flowers 
small,  pale  blue,  on  slender  pedicels:  capsule  swollen,  many-seeded.  Com- 
mon in  and  about  brooks  and  swampy  ground.    June  through  summer. 

V.  officinalis,  Linn.  Little  pubescent  prostrate  perennial,  6  in.  to  1  ft., 
in  dry  fields  and  woods:  leaves  wedge-oblong,  or  obovate,  short-petioled, 
serrate:  racemes  spike-like,  longer  than  leaves;  flowers  pale  blue.    July. 

V.  peregrina,  Linn.  Annual,  glabrous,  erect,  4-9  in.,  branched:  lower 
leaves  thick,  oval,  toothed,  petioled;  others  sessile,  entire:  flowers  very  small, 
whitish,  axillary  and  solitary:  capsule  orbicular,  slightly  notched.  A  common 
weed.   April  to  June. 

V.  serpyllifolia,  Linn.  Perennial,  creeping;  leaves  small,  rounded, 
almost  entire:  flowering  stems  smooth,  simple,  ascending  2-6  in.;  flowers 
very  small,  in  terminal  racemes;  corolla  pale  blue  or  whitish  with  purple 
stripes,  exceeding  calyx.  Common  in  lawns  and  grassy  fields.  May,  through 
summer. 


XXXVI.  SOLANACE^.   Nightshade  Family. 

Herbs  or  shrubs,  with  alternate  often  compound  leaves:  flowers 
perfect  and  regular,  5-merous,  mostly  rotate  or  open-bell -shaped 
in  form  and  plaited  in  the  bud;  stamens  5,  often  connivent  around 
the  single  2-loculed  pistil,  borne  on  the  corolla:  fruit  a  berry  or  cap- 
sule (the  latter  sometimes  4-loculed  by  a  false  partition),  the  seeds 
borne  on  a  central  column.  Some  70  genera  and  1,500  species.  Com- 
mon representatives  are  nightshade,  potato,  tomato,  husk  tomato, 
tobacco,  jimson-weed,  petunia. 

a.  Fruit  a  fleshy  berry. 

b.  Fruiting  calyx  bladdery-inflated  and  wholly  inclosing 
the  fruit;  anthers  not  connected,  opening  length- 
wise  I.  Physalis 

BB.  Fruiting  calyx  not  inflated. 


SOLANACE.E  409 

c.  Stamens  with  anthers  equaling  or  exceeding  the 
filaments. 
D.  Anthers  separate  or  barely  connected,   opening 

at  the  top 2.  Solanum 

dd.  Anthers  united,  opening  lengthwise 3.  Lycopersicum 

cc.  Stamens  with  anthers  much  shorter  than  filaments. 4.  Capsicum 
aa.  Fruit  a  capsule. 

b.   Calyx  5-parted  to  near  base 5.  Petunia 

bb.  Calyx  toothed,  not  deep-parted. 

c.  Pod  usually  prickly,  large 6.  Datura 

cc.  Pods  not  prickly,  small 7.  Nicotiana 

1.  PHtfSALIS.    Ground  Cherry. 

Herbs,  flowering  through  the  summer:  flowers  solitary,  nodding  on 
axillary  peduncles:  leaves  alternate  or  often  somewhat  paired,  margins 
entire  or  sinuate:  calyx  enlarging  after  flowering,  and  finally  inclosing  the 
pulpy  berry  as  a  much-inflated  papery  sac;  corolla  yellowish  or  white,  often 
with  dark  center,  wheel-shaped,  with  short  tube,  the  border  obscurely 
5-lobed,  plaited  in  bud. 

P.  virginiana,  Mill.  Perennial  by  rootstocks,  viscid:  fruiting  calyx 
pyramidal,  closed,  more  or  less  5-angled  and  indented  at  base:  berry  reddish 
yellow,  edible,  not  filling  the  loosely  inflated  calyx:  corolla  yellow,  nearly 
an  inch  in  diameter,  with  brown  center,  and  edge  5-  to  10-angled:  anthers 
yellow.    Open  places,  in  rich  soil.    Summer. 

P.  pubescens,  Linn.  Low  annual,  more  or  less  pubescent  and  clammy: 
stem  generally  diffuse  in  branching,  9-18  in.  tall,  often  somewhat  swollen  at 
nodes:  corolla  small,  about  J*j  in.  across,  yellow  or  greenish,  with  a  dark, 
spotted  center;  anthers  purple:  the  green  or  yellow  berry  does  not  fill  the 
closed,  5-angled  calyx.    In  low  or  damp  places. 

2.  SOLANUM.    Nightshade. 

Perennials  or  annuals:  calyx  and  corolla  5-parted,  the  latter  rotate; 
Btamens  5,  exserted,  the  anthers  separate  and  opening  by  a  pore  in  the  top: 
berry  2-loculed. 

a.  Plants  not  prickly. 

S.  tuberosum,  Linn.  Potato.  Figs.  24,  45,  242.  Low,  diffuse-growing 
perennial,  producing  stem-tubers  on  slender  underground  rootstocks:  leaves 
pinnate,  the  leaflets  differing  in  size  and  ovate:  flowers  bluish:  berries  globu- 
lar, yellowish  green.  Warm  temperate  elevations  of  tropical  America.  The 
"Irish,"  "white"  or  "round"  potato. 

S.  nigrum,  Linn.  Common  nightshade.  Branchy  annual,  1-2  ft.,  nearly 
smooth:  leaves  ovate,  wavy-margined:  flowers  small,  white:  berries  small, 
black.    Waste  places. 

S.  Dulcamara,  Linn.  Bittersweet.  Fig.  424.  Tall,  loosely  climbing:  leaves 
cordate-ovate,  sometimes  3-lobed,  often  with  2  or  4  small  leaflets  at  the  base: 
flowers  email,  violet-purple:  berries  oval,  red.    Perennial.    Common. 


410 


THE    KINDS    OF    PLANTS 


547.  Capsicum  annuum. 


aa.  Plants  prickly. 
S.  Melongena,  Linn.    Eggplant.   Guinea  squash.   Fig.  288.   Stout  annual 
with  large,  ovate,  somewhat  angled  pubescent  leaves:  flower  large,  purplish, 
the  calyx  prickly:  fruit  a  very  large  purple  or  white  berry  (often  weighing 
several  pounds).    India. 

3.  LYCOPERSICUM.   Tomato. 

Differs  from  Solanum  chiefly  in  having  the  anthers 
united  at  their  tips  by  a  membrane  and  opening  by 
lengthwise  slits. 

L.  esculentum,  Mill.  Common  tomato  plant.  Tall, 
hairy,  strong-smelling  herb,  with  pinnate  leaves,  the 
leaflets  ovate  and  unequal -sided  and  of  different  sizes: 
flowers  small,  yellow,  in  short  forked  racemes:  fruit  a 
large  red  or  yellow  berry.    South  America. 

4.  CAPSICUM.    Red  Pepper. 

Erect,  branchy,  smooth  herbs:  stamens  with  slender  filaments  which 
are  much  longer  than  the  separate  anthers,  the 
latter  opening  by  lengthwise  slits:  fruit  globular, 
long  or  irregular,  firm. 

C.  annuum,  Linn.  Common  red  pepper.  Fig. 
547.  Annual  or  biennial,  with  ovate  entire  leaves: 
flowers  white,  with  very  short-toothed  or  trun- 
cate calyx:  fruit  very  various  in  the  cultivated 
varieties.    Tropical  America. 

5.  PETUNIA.    Petunia. 

548.   Petunia  nyclaginiflora. 
Clammy-hairy  diffuse  herbs:  calyx-lobes  leaf- 
like and  much  longer  than  the  tube;  corolla  funnelform,  showy,  the  stamens 
not  projecting:    fruit  2-loculed,  capsular.    South  America. 

P-  nyctaginiflora,  Juss.  White  petunia.  Fig.  548.  Corolla  white,  very  long- 
tubed:  leaves  oval-oblong,  narrowed  into  a  petiole. 
P.  violacea.  Lindl.  Fig.  549.  Weaker  and  more 
diffuse:  corolla  purple  or  rose,  the  tube  short  and  broad: 
leaves  ovate  or  oval,  nearly  or  quite  sessile.  The  gar- 
den petunias  are  mostly  hybrids  of  the  2  species. 

6.  DATURA.   Jamestown-weed  or  Jimson-weed. 

Very  strong  bushy  herbs,  with  large,  long-tubular, 
short-lived  flowers  from  the  forks  of  the  branches: 
stigma  2-parted:  fruit  a  globular  usually  prickly  cap- 
sule, opening  by  4  valves. 

D.  Stramonium,  Linn.  Fig.  275.  Annual,  3-5  ft., 
the  stem  green:  leaves  ovate,  sinuate  or  angled:  corolla 
white.    Tropics;  common  weed. 

D.  Tatula,  Linn.    Stem  and  corolla  purple. 


549.    Petunia. 

Very  near  the  original 

P,  violacea. 


SOLANACE.E — CONVOLVULACE^E 


411 


ez. 


7.  NICOTlANA.   Tobacco. 

Tall    herbs,  with   large  usually   pubescent   leaves: 
corolla  funnelform  or  salverform,  the  tube  usually  long: 
stigma    not    lobed:    pod    2-4-valved,    not   very   large,    s^> 
contained  within  the  persistent  calyx. 

N.  Tabacum,  Linn.  Tobacco.  Robust  annual,  4-6 
ft.,  with  very  large  ovate  decurrent  entire  leaves  and 
rose-purple  panicled  flowers.    Tropical  America. 

N.  aluta,  Link  &  Otto  (N.  affini*  of  gardens).  Fig. 
550.  Slender  but  tall  (2-4  ft.)  plant  with  clammy- 
pubescent  herbage:  leaves  lanceolate  or  obovate, 
entire:  flowers  white,  with  very  slender  tube  5-6 
in.  long,  the  limb  unequal.  Brazil;  common  in 
gardens. 


550.    Nicotiana  alata. 


XXXVII.  CONVOLVULACE.E.   Convolvulus  Family 


Herbs,  mostly  twining,  with  alternate  chiefly  simple  leaves:  flow- 
ers regular,  5-merous,  the  tubular  or  trumpet-shaped  corolla  mostly 
twisted  in  the  bud,  the  stamens  5  and  borne  on  the  corolla;  ovary 
commonly  1-,  mostly  2-loculed,  with  2  ovules  in  each  locule,  becom- 
ing a  globular  capsule  in  fruit  (which  is  sometimes  4-loculed  by  the 
insertion  of  a  false  partition).  The  family  contains  between  30  and 
40  genera,  and  nearly  1,000  species.  Common  convolvulaceous  plants 
are  morning-glory,  cypress  vine,  sweet  potato,  bindweed,  dodder. 

A.  Plants  with  normal  foliage. 

B.  Stigma  2-3-lobed,  knobbed:  calyx  not  bracted 1.  Ipomoea 

bb.  Stigmas  2,  thread-form:  calyx  sometimes  inclosed  by  2 

leafy  bracts '. 2.  Convolvulus 

aa.  Plants  leafless,  parasitic 3.  Cuscuta 

1.  IPO M <E A.    Morning-glory. 

Mostly  twining,  with  showy  flowers  on  axillary  peduncles: 
corolla  with  a  long  tube  and  a  flaring  limb;  pistil  1,  with  one 
style,  and  the  stigma  2-3-lobed:  fruit  a  capsule,  with  1-seeded 
locules. 

a.  Leaves  compound,  with  thread-like  divisions. 
I.  Quamoclit,  Linn.    Cypress  vine.    Fig.  551.    Leaves  pin- 
nate:  flowers  solitary,  red,   small,    narrow-limbed,    with  pro- 
jecting style  and  stamens.    Tropical   America,  but  run  wild 
South;  also  cultivated.     Annual. 

aa.  Leaves  simple  or  deeply  lobed,  broad. 
551.   Ipomcea  '«   Bdna-N6x,   Linn.     White  moon/lower.     Fig.   552.     Tall: 

Quamoclit.        leaves  heart-shaped,    or   angled   or   lobed:   flowers    1    to   few, 


412 


THE    KINDS    OF    PLANTS 


white,  opening  once  at  night,  with  a  slender  tube  and  a  large  limb  4-6  in. 
across.    Tropical    America.    Perennial. 

I.  purpurea,  Roth.  Morning-glory.  Fig.  240.  Leaves 
broadly  cordate-ovate,  entire:  flowers  2-4,  large  and  fun- 
nel-shaped, 2-3  in.  long,  purple  to  streaked  and  white. 
Tropical  America.    Annual. 

I.  hederacea,  Jacq.  Leaves  heart-shaped,  3-5-lobed: 
flowers  1-3,  rather  smaller  than  those  of  /.  purpurea. 
Tropical  America.    Annual. 

I.  Batatas,  Poir.  Sweet  potato.  Fig.  204.  Creeping: 
leaves  heart-shaped  to  triangular,  usually  lobed:  flowers 
(seldom  seen)  3  or  4,  light  purple,  funnel-form,  1^  in.  long. 
Tropics;  grown  for  its  large  edible  root-tubers. 


552.    Ipomoea 
Bona-Nox. 


2.  CONVOLVULUS.    Bindweed. 

Herbs  (or  shrubs)  twining  or  erect:  flowers  large,  on  axillary  peduncles; 
sepals  5;  corolla  funnelform  or  bell-form,  limb  entire,  5-angled  or  5-lobed; 
stamens  inserted  on  corolla-tube,  included;  style  1;  stigmas  2,  long;  ovary 
and  pod  2-celled,  4-seeded. 

C.  sepium,  Linn.  Rutland  beauty.  Perennial:  twining  or  trailing  stem: 
leaves  heart-shaped  or  arrow-shaped,  auricles  often  toothed:  flowers  axil- 
lary and  solitary  on  a  peduncle;  calyx  with  2  large  bracts  at  base,  inclosing 
it;  corolla  morning-glory-like,  white  or  pink,  >£-2  in.  long,  margin  quite 
entire.    Wild  in  low  grounds.    Summer. 

C.  arvensis,  Linn.  Bindweed.  Perennial,  nearly  glabrous,  prostrate  or 
climbing:  leaves  entire  arrow-shaped,  with  basal  ears  acute-lobed,  but  vari- 
able: calyx  not  bracted  at  base;  corolla  pink,  nearly  white,  small, 
not  over  1  in.  long.    Europe.    Bad  weed.    May  to  September. 

3.  CUSCUTA.   Dodder. 

Parasitic  twiners  without  foliage  (leaves  reduced  to  scales): 
flowers  in  clusters,  the  calyx  and  corolla  with  4-5  lobes:  fruit  2- 
loculed,  4-seeded. 

C.    Gronovii,    Willd.    (Fig.    553),    is    the    commonest    species, 
twining    its    slender    coral-yellow    stems   over   coarse 
herbs  in  swales:  corolla  bell-shaped,  the  tube  longer 
than  the  blunt  and  spreading  lobes. 


XXXVIII.  BORRAGINACE.E.   Borage  Family. 

Generally  rough  herbs,  with  round  sterns,  leaves 
usually  alternate  and  hairy,  exstipulate:  inflores- 
cence commonly  1-sided,  in  coiled  terminal  racemes, 
straightening  as  flowers  open;  lobes  of  calyx  5:  lobes 
of  corolla  5,  usually  regular;  stamens  5,  on  corolla- 


553.   Cuscuta      |]' 
Gronovii. 


BORRAGINACEiE  413 

tube;  ovary  deeply  4-lobed,  with  style  in  center;  stigmas  1  or  2:  fruit 
usually  4  separate  1-seeded  nutlets  at  bottom  of  persistent  calyx. 
About  1,500  species  and  80  genera. 

A.  Ovary  entire,  style  terminal:  fruit  dry  nutlets  (2  or  4).l.  Heliotropium 
aa.  Ovary  deeply  4-parted,  or  4-divided,  the  style  rising 
from  the  center. 

B.  Corolla  and  stamens  regular. 

c.  Fruits  (nutlets)  bur-like,  prickly  or  spiny. 

d.  Nutlets  oblique,  fixed  by  apex,  or  laterally, 

to  style,  covered  all  over  by  hooked  prickles. 2.  Cynoglossum 
dd.  Nutlets  erect,  fixed   by  base  or  side  to  the 
central  column:  prickles  in  1  or  more  rows 

on  the  surface 3.  Lappula 

CC.  Fruits  (nutlets)  not  armed  with  prickles. 

D.   Nutlets  attached  laterally  to  the  .receptacle: 

flowers  rather  large 4.  Mertensia 

dd.  Nutlets  attached  by  bases  to  receptacle. 

E.  Flowers  not  bracted,  in  racemes    5.  Myosotis 

ee.  Flowers  bracted,  in  racemes 6.  Lithospermum 

bb.  Corolla  irregular:  stamens  unequal 7.  Echium 

1.  HELIOTROPIUM.    Heliotrope. 

Perennial  or  annual  herbs  (or  shrubs)  with  white  or  purplish,  small 
flowers  in  1-sided  spikes:  flowers  alternate,  usually  entire;  stamens  short, 
anthers  nearly  sessile;  style  short,  with  conical  stigma;  ovary  4-celled: 
fruit,  4  nutlets  or  two  2-celled  nutlets. 

H.  peruvianum,  Linn.  Common  garden  heliotrope.  Pubescent  or  rough, 
often  rather  shrubby:  leaves  lance-ovate  to  oblong,  short-petioled,  veiny 
and  wrinkled:  flowers  very  fragrant,  white  to  lilac. 

2.  CYNOGL6SSUM.   Hound's  Tongue.   Stick-tight. 

Tall,  coarse,  usually  rough  and  unpleasantly  scented  hairy  weeds,  with 
large  entire  alternate  leaves:  flowers  small,  inconspicuous,  in  racemes  or 
forked  cymes,  some  bracted;  corolla  short,  nearly  wheel  form,  with  5  con- 
verging, blunt  scales  closing  the  throat;  ovary  deeply  4-parted,  with  style 
from  center:  fruit  of  bur-like  nutlets,  covered  with  hooked  prickles. 

C.  officinale,  Linn.  A  coarse,  pubescent,  troublesome  dock-like  weed 
from  Europe,  dull  green,  smelling  like  mice,  grows  to  1  or  2  ft.,  leafy  to 
the  top:  leaves  softly  pubescent,  lance-oblong,  mostly  sessile:  corolla  dull 
reddish  purple,  not  %  in.  across:  nutlets  margined.    Biennial. 

C.  virginianum,  Linn.  Stem  stout,  2-3  ft.  tall,  bristly  hairy,  leafless 
above:  leaves  oblong  oval  with  clasping  bases:  flowers  pale  blue,  bractless, 
on  short  pedicels  in  terminal  short  spikes:  nutlets  not  margined.    Perennial. 

3.  LAPPULA  (Echinospermum).    Stick-seed.    Bur-seed. 

Annual  or  biennial  weeds  in  dry  soils,  grayish  with  hairs:  leaves  alter- 
nate, narrow,  entire:  flowers  small,  blue  or  white,  in  terminal,  leafy-bracted 


414  THE     KINDS    OF    PLANTS 

racemes:  corolla  with  5  scales  in  throat:  nutlets  erect,  bearing  1-3  rows  of 
stout  prickles,  and  fixed  by  side  to  the  central  column. 

L.  virginiana,  Lehm.  A  troublesome  biennial  or  annual  weed  of  thickets 
and  open  woods,  2-4  ft.,  slender  and  branching:  leaves  thin,  oblong-ovate, 
tapering  at  both  ends:  flowers  small,  whitish  or  bluish,  on  pedicels,  in 
racemes  1-3  in.  long,  reflexing  in  fruit:  nutlets  small,  globose,  covered 
with  barbed  prickles. 

4.  MERTENSIA.    Lungwort. 

Perennial,  usually  glabrous  herbs,  with  leaves  entire,  pale  green  and 
often  dotted,  the  radical  ones  many-veined  and  the  stem-leaves  sessile: 
flowers  in  terminal  racemes;  calyx  short,  5-cleft;  corolla  funnelform  or 
trumpet-shape,  often  with  5  small  folds  in  throat,  and  stamens  inserted 
between;  style  long  and  slender:  nutlets  erect,  smooth,  finely  wrinkled. 

M.  virginica,  DC.  Leaves  entire,  obovate,  sessile  on  stem:  flowers  large, 
trumpet-shaped,  1  in.  long,  spreading  or  hanging  on  slender  pedicels,  light 
blue  or  pinkish;  corolla-throat  not  crested,  limb  entire.  Perennial.  Rich 
soil.    May,  June. 

5.  MYOSOTIS.    Forget-me-not. 

Low,  usually  villous  herbs,  with  stems  erect  or  reclining,  branching: 
leaves  small,  alternate,  entire:  flowers  small  in  bractless  racemes;  corolla 
salver-form,  5-lobed,  lobes  spreading,  rounded  with  appendages  at  base: 
nutlets  smooth  or  hard,  fixed  by  base.    Several  species. 

M.  scorpioides,  Linn.  (M.  palustris.  With.).  True  forget-me-not.  A 
favorite  garden  perennial  introduced  from  Europe,  but  also  escaped  to  field 
and  moist  spots:  racemes  1-sided:  leaves  lance-oblong,  obtuse:  calyx  open  in 
fruit,  the  lobes  shorter  than  the  tube:  corolla  light-blue,  with  yellow  center. 

M.  laxa,  Lehm.  Flowers  smaller,  paler,  on  long  pedicels:  calyx-lobes 
long:  habit  lax.    Swamps. 

M.  arvensis,  Hoffm.  Hairy:  leaves  lance-oblong,  acute:  calyx  closing  in 
fruit  and  beset  with  minutely  hooked  bristles.    Fields,  native. 

6.  LITHOSPERMUM.    Gromwell.    Puccoon. 

Hairy  herbs  with  roots  usually  red:  leaves  alternate,  entire:  flowers  in 
leafy-bracted  racemes  or  spikes;  calyx-segments  5,  narrow;  corolla  funnel- 
or  salver-form,  5-lobed,  sometimes  crested  in  throat;  stamens  5,  with  short 
filaments,  included  on  corolla-throat;  stigma  2-lobed:  nutlets  4,  smooth 
or  wrinkled,  usually  stony. 

L.  arvense,  Linn.  Rough  weed  from  Europe,  8-12  in.:  leaves  small,  lan- 
ceolate to  linear:  flowers  insignificant:  corolla  white,  hardly  as  long  as  calyx, 
without  appendages  in  throat:  nutlets  roughly  wrinkled,  dull  gray. 

L.  Gmelinii,  Hitchc.  (L.  hirtum,  Lehm.).  A  rough,  native  perennial,  with 
simple  stem,  8  in.  to  2  ft.,  on  dry,  sterile  ground:  leaves  lanceolate  or  linear, 
hairy:  flowers  densely  crowded  in  short  terminal  leafy  racemes:  corolla  bright 
orange-yellow,  showy,  longer  than  calyx,  with,  little  appendages  in  throat, 
§nd  woolly.  June, 


BORRAGINACEiE — HYDROPHYLLACEjE  415 

L.  canescens,  Lehm.  Puccoon.  Not  so  rough  as  preceding,  but  hoary, 
6-18  in.  high:  flowers  yellow  axillary  smaller  and  corolla-throat  appendaged, 
hut  not  bearded.  Grows  in  open  woodlands  and  fields,  Canada  to  Alabama 
and  West. 

7.  ECHIUM.   Viper's  Bugloss. 

Stout  and  coarse  herbs:  leaves  alternate,  entire:  flowers  rather  large, 
usually  blue  or  purplish,  in  spicate  or  panicled  racemes;  calyx-segments  5, 
narrow;  corolla  irregular,  with  5  unequal  lobes,  short-tubed,  and  throat  not 
bearded;  stamens  5,  unequal,  and  long-exserted;  stigmas  2  or  2-lobed: 
nutlets  4,  erect,  rough-wrinkled. 

E.  vulgare,  Linn.  Stems  1-3  ft.  erect,  leafy,  very  bristly  hairy:  leaves 
lanceolate,  sessile  on  stem,  4-8  in.  long:  flowers  bright  purplish,  chang- 
ing to  bright  blue  in  1-sided  spikes.  Biennial;  early  summer.  Naturalized 
from  Europe,  and  becoming  a  showy  but  troublesome  weed  in  places. 


XXXIX.  HYDROPHYLLACE.E.   Waterleaf  Family. 

Mostlv  hirsute  or  scabrous  herbs,  with  good-sized  mostly  alter- 
nate, simple  or  compound  leaves:  flowers  regular,  5-parted,  in  1-sided 
cymes,  spikes  or  racemes;  ovary  superior,  1-celled,  with  2  parietal 
placentae,  or  apparently  2-celled;  styles  2  or  2-cleft:  capsule  usually 
loculicidally  2-valved.  Nearly  200  species,  but  only  1  genus  frequent 
in  northeastern  states. 

HYDROPHYLLUM.   Waterleaf. 

Perennial,  usually  found  in  rich,  low  woods:  leaves  large,  petioled: 
cymes  more  or  less  coiled:  calyx  often  with  small  appendages  at  the  notches 
of  the  lobes;  corolla  bell-shape,  5-cleft,  usually  convoluted  in  bud  and  bear- 
ing 5  folds  or  scales  inside  the  tube;  style  and  stamens  (with  hairy  filaments) 
projecting.  In  shady  places,  these  interesting  plants  make  heavy  masses 
of  foliage. 

H.  macrophyllum,  Nutt.  A  hoary-hairy  plant,  about  1  ft.  tall,  branching: 
leaves  pinnately  cut:  flower-cluster  on  long  stout  peduncle:  corolla  white 
or  bluish,  about  1  in.  across:  sepals  not  appendaged  at  base:  stamens  longer 
than  corolla. 

H.  appendiculatum,  Michx.  Hairy,  1-1  ^  ft.  tall:  leaves  large,  mostly 
5-lobed  or  angled,  some  of  the  lower  ones  pinnately  parted:  flower  clusters 
loose ;  corolla  blue ;  sepals  appendaged  at  bases,  bristly  hairy ;  stamens  not 
much  if  any  longer  than  corolla. 

H.  canadense,  Linn.  About  1  ft.  high,  smoothish:  leaves  all  rounded, 
with  5-9  shallow  lobes,  and  heart-shaped  bases,  or  with  small  leaflets  on  the 
petioles:  corolla  white  or  purplish.  //.  virginicum,  Linn.,  is  closely  allied, 
but  has  pinnately  divided  leaves. 


416  THE     KINDS     OF     PLANTS 


XL.  POLEMONIACE.E.   Phlox  Family. 

Herbs,  mostly  annuals  or  perennials:  flowers  regular,  in  terminal 
clusters,  5-parted,  with  corolla  monopetalous;  stamens  on  corolla- 
tube,  alternate  with  lobes;  ovary  3-celled;  style  simple  and  3-lobed: 
capsule  3-celled,  with  3,  mostly  loculicidal,  valves.  About  200  species 
in  several  genera.    Phlox  is  the  leading  genus. 

a.  Leaves  entire,  mostly  opposite:  stamens  unequally  in- 
serted on  tube  of  the  corolla 1.  Phlox 

aa.  Leaves  pinnately  compound,  alternate:  stamens  equally 

inserted  on  the  corolla-tube 2.  Polemonium 

1.  PHLOX.    Fig.  241. 

Erect  or  diffuse  herbs,  stems  leafy:  leaves  without  stipules,  entire, 
mostly  sessile,  opposite,  or  alternate  above:  flowers  of  different  colors,  in 
terminal  clusters;  corolla  salver-form,  tube  long;  stamens  5,  unequal, 
included  in  tube.    P.  Drummondii  is  annual;  the  others  perennial. 

P.  paniculata.  Linn.  Stems  2-4  ft.  high,  usually  stout  and  in  clumps: 
leaves  ovate-lanceolate,  or  oblong:  flowers  on  short  pedicels  in  many-flow- 
ered panicled  cymes,  terminal,  white  to  various  pinks  and  reds;  calyx-teeth 
sharp-pointed;  lobes  of  corolla  rounded  and  entire. 

P.  maculata,  Linn.  One  to  2  ft.  high:  stem  spotted  with  purple:  lower 
leaves  the  heavier,  lanceolate-linear;  upper  taper-pointed  with  a  heart- 
shaped  sessile  base:  panicle  elongated,  pyramidal,  of  many  pink-purple 
flowers;  calyx-teeth  less  pointed  than  in  preceding:  corolla-lobes  entire. 
All  summer.  This  and  the  preceding  species  are  the  originals  of  the  common 
perennial  phloxes  of  gardens. 

P.  divaricata,  Linn.  Ascending  or  diffuse  to  1  ft.,  or  more,  terminating 
in  loose  corymb,  rather  sticky -pubescent:  leaves  ovate-oblong  or  broad-lan- 
ceolate, rounded  at  base,  acute  at  tip,  sessile,  pubescent:  corolla  large,  gray- 
ish blue  or  lilac,  the  lobes  notched;  calyx-teeth  slender  and  longer  than 
tube.    Moist  woods.    Spring. 

P.  subulata,  Linn.  Ground  or  moss  pink.  Stems  creeping,  tufted,  much 
branched  and  leafy,  forming  a  moss-like  carpet  over  the  ground:  leaves 
about  y$  in.  long,  rigid,  linear  to  awl-shaped,  spreading  in  clusters:  flowers 
3-6  in  depressed  clusters,  white  to  pinkish-purple;  lobes  of  corolla  shorter 
than  tube.    Spring. 

P.  Drummondii,  Hook.  From  Texas,  now  the  common  annual  phlox  in 
gardens:  stems  branching,  spreading,  about  1  ft.  high,  rather  downy-clammy: 
flowers  showy,  in  corymbs;  various  colors  and  patterns  on  the  corolla  and 
lobes  variously  notched. 

2.  POLEMONIUM. 

Perennial  herbs,  with  alternate  pinnately  compound  leaves:  calyx  com- 
panulate,  segments  erect  over  fruit;  corolla  bell-form  or  rotate;  stamens 


POLEMONIACE.E — ASCLEPIADACE.E  417 

slender,  declined,  hairy  at  base,  inserted  on  corolla  base.  The  following 
native  perennials  are  often  cultivated. 

P.  reptans,  Linn.  Greek  valerian.  Stems  rather  weak,  diffusely  branch- 
ing (not  creeping),  6  in.  to  \l/$  ft.:  leaves  smooth,  of  7-13  leaflets,  occa- 
sionally a  simple  one:  leaflets  lance-ovate  or  oblong,  about  1  in.  long,  with 
entire  margins:  flowers  nodding,  light  blue  corolla  .'5  times  as  long  aa 
calyx,  not  over  }  2  in.  broad. 

P.  Van  Briintiae,  Hrit.  Jacob's  ladder.  Tall,  erect  to  1-3  ft.,  smooth  or 
hairy:  leaflets  9-17,  lanceolate,  crowded:  flowers  bright  blue,  in  erect 
long  panicles;  stamens  and  style  longer  than  corolla-lobes;  corolla  1  in. 
broad. 

XLI.  GENTIANACE.E.   Gentian  Family. 

Generally  smooth  herbs,  with  bitter,  colorless  juice  (tonic  proper- 
tics):  entire  leaves  mostly  opposite,  sessile  and  without  stipules: 
flowers  regular,  solitary  or  in  clusters;  calyx  persistent;  corolla  mono- 
petalous,  with  4-8-lobed  margin,  and  with  4-8  stamens,  inserted 
on  tube:  capsule  2-valved,  many-seeded.  Some  600  species,  many 
very  showy. 

GENTlANA.    Gentian. 

Herbs  in  low  woods  and  damp  grounds,  flowering  mostly  in  autumn: 
flowers  solitary  or  in  clusters  and  showy,  usually  blue;  corolla  tubular, 
lobes  4-7,  open  or  closed,  some  having  a  membranous  fold  in  each  of  the 
notches  of  the  limb;  stamens  4-7:  style  short  or  wanting. 

G.  crinita,  Froel.  Fringed  gentian.  Annual,  in  moist  soil,  blooming  in 
September  and  October:  distinguished  by  the  beautiful  flowers,  solitary  and 
terminal  on  erect  stems  (stems  about  1  ft.  tall),  pure  blue,  lJ^-2  in.  long, 
funnelform,  with  4  spreading  lobes,  having  the  margins  cut  into  a  fringe 
all  around:  leaves  clear  green,  lanceolate,  acute,  sessile. 

G.  procera,  Holm.  Similar  to  the  preceding,  but  smaller  and  corolla 
less  fringed:  leaves  linear. 

G.  Andrewsii,  Griseb.  Closed  gentian.  Perennial:  stems  simple,  smooth, 
to  about  1 !  2-2  ft.:  leaves  ovate  to  lanceolate,  with  narrow  base:  flowers 
in  terminal,  sessile  clusters:  corolla  blue  with  notched  folds  or  appendages 
on  the  margin,  never  opening. 


XLII.  ASCLEPIADACE.E.    Milkweed  Family. 

Perennial  herbs  or  shrubs,  often  vines,  with  milky  juice:  leaves 
opposite  or  sometimes  whorled,  exstipulatc:  flowers  generally  in  umbels, 
regular  and  5-parted,  but  very  peculiar  in  the  structure  and  connection 
of  stamens,  stigma  and  pollen:  hood-like  appendages  are  borne  be- 
hind the  anthers,  forming  a  corona  about  the  stigma;  stamens  5  with 


418  THE     KINDS    OF    PLANTS 

very  short  filaments,  and  mostly  monadelphous;  the  anthers  press 
against  the  fleshy  5-angled  stigma,  and  the  pollen  coheres  in  waxy  or 
granular  masses,  1  or  2  to  each  anther-sac:  fruit  of  1  or  2  follicles: 
seeds  bearing  long  silk  (Fig.  303).    About  2,000  species  and  200  genera. 

ASCLfiPIAS.    Milkweed.    Silkweed. 

Erect  perennial  herbs,  with  mostly  opposite,  thick  simple  leaves  and 
flowers  in  simple  umbels:  calyx  and  corolla  each  with  5  lobes,  bent  down- 
ward, leaving  the  crown  of  5  hood-like  appendages,  each  bearing  a  horn, 
conspicuously  surrounding  the  stamens;  filaments  generally  united,  and 
the  anthers  adherent  to  the  fleshy  stigma;  anther  2-celled  and  each  cell  con- 
taining a  firm,  waxy,  elongated  mass  of  pollen;  adjacent  pairs  of  the  pollen- 
masses  are  connected  and  suspended  from  one  of  5  glands  resembling  a  pair 
of  saddle-bags.  The  flower  is  peculiarly  adapted  to  insect-pollination,  the 
pollen-masses  being  carried  on  the  feet  of  insects. 

A.  tuberosa,  Linn.  Butterfly  weed.  Pleurisy  root.  About  2  ft.,  with  most 
conspicuous  erect  clusters  of  brilliant  orange  flowers:  leaves  irregularly  scat- 
tered on  stems,  or  alternate,  linear  or  lance-oblong,  hairy,  sessile:  pods 
nearly  erect,  finely  pubescent.    Dry  fields  and  hillsides.    Summer. 

A.  incarnata,  Linn.  Swamp  milkweed.  Fig.  271.  A  handsome  milk- 
weed of  wet  grounds:  stems  leafy,  2-5  ft.:  leaves  lanceolate  or  lance-oblong, 
acuminate,  rather  smooth,  opposite:  flowers  rose-colored  to  white,  sweet- 
scented,  in  somewhat  paniculate  umbels:  follicles  erect,  smooth. 

A.  syriaca,  Linn.  (A.  Corniiti,  Decne.).  Common  milkweed.  Fig.  303. 
Stems  3-4  ft.  high,  stout,  very  milky,  usually  simple,  leafy:  leaves  large, 
oblong,  downy  beneath,  stiff,  4-8  in.  long,  opposite,  short-petioled :  flowers 
Yi  in.  long,  greenish-lavender  to  lavender,  with  strong,  sweet,  but  unpleasant 
odor:  pods  rough  or  warty. 

A.  purpurascens,  Linn.  Purple  milkweed.  Stems  erect,  1-3  ft.,  leafy, 
simple  or  branching:  leaves  oblong  or  ovate-oblong  to  elliptical,  pointed, 
short-petioled,  3-6  in.  long:  flowers  large  (*/£  in.),  dull  purple:  pods  smooth. 

A.  variegata,  Linn.  Stems  simple,  smooth,  leafy:  leaves  oval  to  lance- 
oval,  opposite  or  whorled,  petioled,  pale  beneath,  umbels  on  downy  pedun- 
cles: corolla  white,  hoods  roundish,  sometimes  purplish.    Dry  woods. 

A.  quadrifolia,  Jacq.  Stem  1-2  ft.,  nearly  smooth,  and  leafy  below: 
1  or  2  whorls  of  4-ovate,  taper-pointed,  petioled  leaves  near  middle  and 
above  or  below  a  pair  of  smaller  ones:  umbels  few,  loose-flowered;  flowers 
small,  crown  white;  corolla  white,  tinged  with  pink.    Slender. 


XLIII.  APOCYNACE.E.   Dogbane  Family. 

Herbs  and  woody  plants,  some  of  the  commoner  ones  resembling 
milkweeds,  in  having  milky,  acrid  juice,  and  seeds  crested  with  silky 
hairs,  but  filaments  distinct,  pollen  granular,  and  corolla  twisted 
(rather  than  volvate)  in  the  bud:  hairs:  leaves  chiefly  opposite,  entire, 


APOCYNACE.E  419 

simple,  without  stipules:  flowers  regular  and  monopetalous,  solitary 
or  in  cymes,  5-parted;  ovary  of  2  free  carpels;  stigmas  united.  About 
1,000  species  and  120  genera. 

a.  Herbs  erect:  flowers  in  terminal  cymes  or  corymbs 1.  Apocynum 

aa.  Half  shrubby,  trailing  or  erect  plants:  flowers  solitary  in 

axils 2.  Vinca 

AAA.  Cultivated  house  and  garden  shrubs:  erect:  leaves  oppo- 
site, or  whorled  in  3's 3.  Nerium 

1.  AP6CYNUM.    Dogbane. 

Upright  branching  herbs,  with  reddish,  fibrous  bark:  flowers  small, 
white  or  pink,  in  terminal  corymbs:  leaves  opposite,  entire,  acuminate: 
corolla  bell-shaped,  5-lobed,  with  5  small,  triangular  scale-appendages 
within  the  tube,  each  alternating  with  one  of  the  5  stamens  attached  at 
base  of  tube;  ovaries  2,  distinct;  stigma  2-lobed:  pods  long,  .slender  and 
full  of  seeds  which  are  tufted  with  silky  hairs  at  one  end. 

A.  androsaemifolium,  Linn.  Smooth  plants,  2-4  or  5  ft.  tall,  with 
branches  widely  spreading;  stems  usually  purplish:  leaves  2-4  in.  long, 
ovate-acute,  short-petioled:  corolla  small,  %  in.  long,  bell-form,  with  lobes 
spreading  or  recurving,  the  tube  exceeding  the  calyx.  A  very  common 
weed  along  hedge-rows,  in  light  woodlands  and  clearings. 

A.  cannabinum,  Linn.  Indian  hemp.  More  erect:  leaves  oblong  or 
oblong-ovate:  flowers  erect,  with  the  corolla-lobes  scarcely  spreading,  the 
tube  about  the  length  of  the  calyx.    Banks  and  shores. 

2.  VINCA.   Periwinkle. 

Herbs,  creeping  or  erect,  and  more  or  less  woody:  leaves  mostly  ever- 
green and  opposite:  flowers  solitary,  axillary,  5-parted;  style  1;  follicles  2, 
erect,  slender. 

V.  minor,  Linn.  Pcriirinkle.  Myrtle  (improperly).  A  familiar  trailing 
plant  of  the  garden,  lawns  and  cemeteries,  growing  in  shady  places,  and 
spreading  by  creeping  stems:  leaves  evergreen,  oblong-ovate,  shiny:  flowers 
solitary  in  axils,  blue  (rarely  white),  the  corolla  salver-form,  about  1  in. 
across.    Spring  and  early  summer. 

V.  rosea,  Linn.  Erect,  often  20-30  in.  high,  rather  woody  at  base: 
leaves  ovate,  obtuse,  on  long  petioles:  flowers  large,  on  slender  axillary 
pedicels,  white,  white  with  rose  eye,  or  plain  rose-color;  blooming  all  season 
when  grown  in  the  house  or  conservatory,  or  all  summer  in  the  garden. 
Tropics. 

3.  NfiRIUM.    Oleander. 

Shrubs  from  warm  climates,  much  cultivated  in  windows  and  green- 
houses: leaves  lanceolate,  leathery  and  stiff:  flowers  in  terminal  cymes, 
white  or  pink,  single  or  double;  corolla  large,  1-2  in.,  salver-form,  the 
throat  bearing  5  fringed  or  toothed  scales;  ovary  of  2  carpels;  stamens  5, 
the  anthers  tipped  with  awn-like  bristles. 


420  THE     KINDS    OF    PLANTS 

N.  Oleander,  Linn.  Common  oleander.  Leaves  lanceolate:  flowers  large, 
rose-color  or  white,  not  fragrant,  with  crown  segments  not  fringed. 

N.  odorum,  Soland.  Sweet  oleander.  Flower  fragrant,  and  bearing 
crown  segments  which  are  more  fringed,  and  long  anther  appendages. 


XLIV.  OLEACE.E.   Olive  Family. 

Trees  or  shrubs:  leaves  simple  or  pinnately  compound,  opposite: 
flowers  various,  but  regular;  calyx  free  from  ovary,  usually  small  and 
4-lobed,  or  none;  corolla  regular,  4-parted,  or  of  4  distinct  petals,  or 
none;  stamens  2,  with  separate  filaments  inserted  on  petals,  or  hypogy- 
nous:  ovary  2-celled;  style  1,  if  any. 

A.  Shrubs  or  very  small  trees:  leaves  simple:  flowers  perfect. 

B.  Flowers  yellow 1.  Forsythia 

BB.  Flowers  white  or  lilac. 

c.  Fruit  a  dry  pod,  loculicidal 2.  Syringa 

CC.  Fruit  berry-like. 

d.  Flowers    practically    polypetalous;    petals    long, 

narrow;  flowers  drooping 3.  Chionanthus 

dd.  Flowers      gamopetalous;      corolla-tube      funnel- 
form,  4-lobed ;  flowers  erect 4.  Ligustrum 

aa.  Large  forest  trees:  leaves  pinnately  compound:  flowers 

imperfect,  mostly  dioecious:  fruit  a  samara 5.  Fraxinus 

1.  FORSfTHIA. 

Ornamental  shrubs  from  the  Orient,  with  opposite  simple  or  trifoliolate 
leaves:  flowers  perfect,  the  deciduous  calyx  and  the  bell-shaped  corolla  in  4 
parts;  stamens  2  on  base  of  corolla;  style  short:  pod  2-celled,  many-seeded. 

F.  viridissima,  Lindl.  Strong  hardy  shrub,  with  green  branches  covered 
with  showy  yellow  flowers,  separate  on  pedicels  in  early  spring  before 
leaves  appear:  leaves  simple,  lance-oblong:  corolla-lobes  narrow-oblong  and 
spreading;  style  twice  as  long  as  stamens. 

F.  suspensa,  Vahl.  Branches  slender  and  drooping:  corolla-lobes  larger 
and  more  spreading  and  style  shorter  than  in  preceding:  leaves  simple, 
broadly-ovate,  also  frequently  trifoliolate  on  same  bush. 

2.  SYRlNGA.    Lilac. 

Common  ornamental  shrubs,  usually  tall,  with  leaves  simple,  entire, 
opposite:  many  small  fragrant  flowers  in  close  terminal  panicles  or  thyrses; 
calyx  4-toothed;  corolla  salver-form,  tube  long;  limb  4-lobed;  stamens  2,  on 
summit  of  corolla-tube:  fruit  a  4-seeded  flattened  pod,  2-valved;  seeds  flat- 
tened, somewhat  winged  or  margined.  No  native  species.  The  name  Syringa 
is  sometimes  popularly  applied  to  Philadelphus. 

S.  vulgaris,  Linn.  Common  lilac.  Fig.  72,  Well-known  bushy  shrub  from. 


OLEACE.E  421 

eastern  Europe:  flowers  purple,  lilac  to  white,  in  dense  upright  thyrses,  very 
fragrant:  leaves  heart-shaped,  entire,  smooth. 

S.  persica,  Linn.  Persian  lilac.  Less  bushy,  and  more  slender  than 
the  common  lilac:  leaves  lance-ovate,  the  bases  tapering:  and  pale  lilac 
or  white  flowers  in  loose  clusters  appearing  later. 

3.  CHIONANTHUS.   Fringe-tree. 

Shrub  or  small  tree  with  opposite,  simple,  entire,  petioled  leaves:  flowers 
in  large  loose  axillary  rather  drooping  panicles;  calyx  small,  persistent; 
corolla  white,  with  4  long,  narrow  petals,  scarcely  united  at  base;  stamens 
2-4,  but  scarcely  adherent  to  corolla  base:  drupe  usually  1-seeded.  A  hand- 
some bush. 

C.  virginica,  Linn.  Native  to  moist  southern  woods,  but  cultivated 
for  ornament:  leaves  oval  to  oblong,  3-5  in.  long:  panicles  with  some  leafy 
bracts;  flowers  conspicuous,  in  spring,  appearing  with  leaves;  petals  1  in. 
long. 

4.  LIGUSTRUM.    Privet.    Prim. 

Stiff  shrubs  or  very  small  trees:  leaves  simple,  entire,  firm  and  thickish, 
short-pet ioled,  opposite:  flowers  small,  white,  in  terminal  thyrses  or  pan- 
icles: calyx  small,  minutely  toothed  or  truncate;  corolla  funnelform,  4-lobed, 
spreading;  stamens  2,  inserted  on  corolla-tube;  ovary  2-celled:  fruit  a 
1-4-seeded,  black  berry. 

L.  vulgare,  Linn.  Leaves  thick,  elliptic-lanceolate,  abundant,  persistent, 
but  deciduous:  flowers  M  in.  wide  and  white;  calyx  smooth:  berries  black. 
Eastern  Europe.    Used  mostly  for  hedges. 

5.  FRAXINUS.   Ash.    Figs.  92,  141. 

Deciduous  tree,  some  of  them  valuable  for  timber:  leaves  odd-pinnate, 
petiolate:  flowers  small,  insignificant,  dioecious  (polygamous  in  some  species), 
racemed  or  panicled — the  American  species  apetalous,  appearing  before  or 
with  the  leaves;  calyx  4-toothed,  small,  seldom  wanting;  stigma  2-cleft: 
fruit  a  flat  1-  (or  2-)  celled  key,  winged.  Several  species  are  native  in 
North  America. 

F.  americana,  Linn.  White  ash.  Forest  tree,  40-80  ft.,  with  rough, 
blackish  bark,  and  gray,  smooth  branches:  leaflets  5-9,  ovate  or  lance-oblong 
and  acuminate,  entire  or  sparingly  serrate,  pale  or  downy  beneath,  smooth 
above,  the  lateral  leaflets  stalked:  flowers  mostly  dioecious,  apetalous;  calyx 
present  in  fertile  flowers,  and  persistent:  fruit  with  lanceolate  wing  at  apex, 
base  nearly  cylindrical,  the  key  1  J>-^— 2  in.  long. 

F.  pennsylvanica,  Marsh.  Red  ash.  A  smaller  tree  than  the  white  ash: 
young  shoots  and  leaf  petioles  and  lower  leaf  surfaces  velvety-pubescent: 
calyx  persistent  on  fertile  flowers:  fruit  narrow,  flattened  at  base,  the  edges 
dilated  into  the  oblanceolate  wing. 

F.  excelsior,  Linn.  European  ash,  often  planted:  leaflets  9-13,  ovate- 
lanceolate  or  oblong,  acute,  serrate:  fruit  oblong,  often  notched  at  end. 


422  THE    KINDS    OF    PLANTS 

XLV.  PRIMULACE^.   Primrose  Family. 

Low  herbs  with  leaves  radical  or  opposite:  flowers  perfect,  reg- 
ular, 5-parted,  monopetalous;  stamens  5,  inserted  in  corolla-tube,  each 
opposite  a  lobe;  style  and  stigma  1;  ovary  1-celled,  superior,  with 
3  central  placentse.   About  300  species  in  some  25  genera. 

a.  Plants  with  all  leaves  basal:  flowers  on  a  scape. 

B.  Corolla-lobes  spreading 1.  Primula 

bb.  Corolla-lobes  reflexed. 

c.  Several  flowers  on  the  scape;  stamens  protmding. .  .2.  Dodecatheon 

cc.  One  flower  on  the  scape;  stamens  included 3.  Cyclamen 

aa.  Plants  with  leafy  stems 4.  Lysimachia 

1.  PRfMULA.   Primrose.    Cowslip  (of  England).   Auricula. 

Low  perennials  herbs,  with  radical  leaves:  flowers  in  an  involucrate 
umbel  in  most  species,  terminal  on  a  scape;  calyx  5-cleft;  corolla  salver- 
shaped,  with  5  spreading  lobes,  entire  or  notched;  stamens  5,  with  short 
filaments  included  in  corolla-tube,  often  of  different  lengths:  capsules 
ovoid,  opening  by  valves  or  teeth  at  the  top.  Native  species  rare,  but  a 
number  of  exotic  primroses  are  much  cultivated. 

P.  sinensis,  Sabine.  Downy  greenhouse  plant:  flowers  in  umbels,  large 
and  showy,  of  different  colors,  single  or  double;  calyx  large  and  inflated: 
leaves  cordate,  7-9-lobed,  on  long  petioles.    China. 

P.  obconica,  Hance.  Leaves  ovate-cordate:  scapes  a  foot  high,  bearing 
pink,  purplish  or  whitish  flowers  in  large  clusters,  the  petals  obconical  and 
notched  at  the  end;  tube  twice  longer  than  the  shallow-spreading  calyx. 
The  hairs  on  this  plant  are  poisonous  to  some  persons.    Greenhouses.    China. 

P.  Forbesi,  Franch.  Baby  primrose.  Scapes  many  and  very  slender, 
6-12  in.,  loosely  hairy,  bearing  small  lilac  or  rose  flowers  in  successive 
whorls  on  slender  pedicels:  leaves  small  and  crowded  at  the  crown,  oblong, 
somewhat  sinuate-toothed.    Greenhouses.    China. 

P.  Polyantha,  Hort.  Polyanthus.  Hardy  primulas,  grown  in  borders  for 
the  early  spring  bloom,  of  hybrid  origin:  leaves  upright,  oblong,  tapering  into 
a  winged  petiole,  shallowly  toothed,  rugose  beneath:  flowers  not  much  over- 
topping the  leaves,  tubular,  with  spreading  limb,  in  shades  of  yellow  and  red. 

2.  DODECATHEON. 

Smooth  perennial  herbs:  leaves  radical,  simple,  oblong  or  spatulate: 
flowers  nodding  in  a  terminal  umbel  on  erect,  unbranching,  leafless  scapes, 
with  involucres  of  small  bracts;  calyx  5-cleft,  lobes  reflexed;  corolla-tube 
very  short,  5-parted,  and  the  segments  strongly  reflexed;  stamens  5,  with 
short  filaments,  united  at  base,  the  anthers  long,  acute  and  uniting  at  tip, 
forming  a  cone;  style  exserted. 

D.  Meadia,  Linn.  Shooting  star.  Wild  in  open  woodland  in  central 
states  and  South  and  West;  also  cultivated;  resembles  Cyclamen  in  the  flow- 
ers, which  are  white  or  rose-purple,  nodding  on  slender  pedicels;  scape  6  in. 
to  2  ft.  high. 


PRIMULACE^E — ERICACEAE  423 

3.  CfCLAMEN. 

Glabrous  plants  from  fleshy  corm:  leaves  all  basal,  rounded,  cordate  or 
ovate:  scapes  bearing  (each)  one  nodding  flower;  corolla-limb  5-parted, 
lobes  turning  back;  anthers  5,  sessile,  not  exserted.  Cultivated  as  house 
plants,  flowering  in  winter. 

C.  latifolium,  Sibth.  &  Sm.  (C.  pirsicum).  Leaves  ovate,  crenate-den- 
tate,  thick,  often  marked  with  white:  flowers  large,  white,  rose  or  purple, 
sometimes  spotted,  oblong.    The  florists'  cyclamen. 

4.  LYSIMACHIA.    Loosestrife. 

Perennials  with  leaves  opposite  or  whorled,  entire,  often  glandular- 
dotted:  flowers  yellow,  solitary  in  axils,  or  panicled;  calyx  5-7-parted; 
corolla  wheel-form;  petals  5-7,  nearly  distinct;  stamens  5-7,  the  filaments 
somewhat  connate  at  base.    Wild  in  low  grounds. 

L.  vulgaris,  Linn.  Erect,  2-3  ft.,  downy:  leaves  3  or  4  in  a  whorl:  flowers 
in  terminal  leafy  panicles;  corolla-lobes  glabrous.  Europe.  Cultivated 
and  escaped. 

L.  quadrifolia,  Linn.  Erect,  1-2  ft.,  hairy:  leaves  lanceolate-ovate,  ses- 
sile, dotted,  commonly  4  in  a  whorl:  flowers  yellow,  with  dark  lines,  on 
Blender  pedicels,  solitary  from  axils  of  upper  leaves.    Damp  soil. 

L.  nummularia,  Linn.  Moneywort.  Trailing  glabrous  perennial:  leaves 
round,  opposite,  on  short  petioles:  flowers  pure  yellow,  axillary  solitary,  on 
short  peduncles;  stamen  filaments  glandular,  connate  at  base.  Running  wild 
in  moist  places,  often  a  weed  in  lawns. 

XLVI.  ERICACEAE.   Heath  Family. 

Plants  of  various  kinds,  many  of  them  shrubs  or  shrubby  herbs, 
Borne  trees,  perennial  herbs,  and  parasites:  leaves  simple  and  often 
evergreen,  or  scale-like:  flowers  most  perfect;  corolla  usually  mono- 
petalous  and  4-  or  5-cleft;  stamens  hypogynous,  as  many  or  twice 
as  many  as  petals,  anthers  usually  opening  by  terminal  pores;  style 
1;  ovary  generally  as  many  celled  as  corolla  has  lobes.  A  large  family, 
represented  by  heaths,  cranberry,  azaleas,  arbutus,  laurel. 

A.  Shrubs,  or  creeping  shrubby  plants. 
B.  Ovary  inferior:  fruit  a  berry. 

c.  Berry  10-seeded 1.  Gaylussacia 

cc.  Berry  many-seeded 2.  Vaccinium 

BB.  Ovary  superior. 

G.  Low  creeping  or  procumbent. 

d.  Fruit  berry-like:  leaves  aromatic 3.  Gaultheria 

dd.  Fruit  dry 4.  Epigsea 

CO.  Shrubs,  erect. 

E.  Corolla    broadly    open,    with    10    little    pouches 

holding  the  anthers 5.  Kalmia 


424  THE    KINDS    OF    PLANTS 

ee.  Corolla   bell-shaped,   no  pockets:   flowers  from 

terminal,  scaly  buds 6.  Azalea 

aa.  Parasitic   herbs,    destitute   of   green   foliage,    about   the 

roots  of  trees 7.  Monotropa 

1.  GAYLUSSACIA.    Low-bush  Huckleberry. 

Shrubs,  low  and  branching,  leaves  and  branches  sometimes  with  resinous 
dots:  leaves  alternate,  entire  or  serrate:  flowers  in  lateral  racemes,  small, 
white  or  pink,  nodding  on  bracted  pedicels,  in  late  spring;  corolla  bell-like 
or  ovoid,  with  5  lobes  erect  or  reflexing;  stamens  10,  usually  included; 
ovary  10-celled:  fruit  berry-like,  containing  10  little  stones,  blue  or  black, 
sweet  and  edible,  ripe  in  late  summer. 

G.  baccata,  C.  Koch.  High-land  huckleberry.  Shrub,  1-3  ft.,  with 
stiff  branches  and  deciduous  entire  oval  leaves,  sprinkled  with  resinous 
dots:  flowers,  in  1 -sided  racemes;  corolla  white,  tinged  with  pink,  cylindrical 
or  somewhat  5-angled,  and  contracted  at  margin:  berry  black,  not  glaucous. 

G.  frondosa,  Torr.  &  Gray.  Tangle-berry.  Shrub,  1-3  ft.,  with  stiff  spread- 
ing branches:  leaves  oblong  to  obovate,  thin,  smooth  and  pale  below, 
resinous-dotted;  corolla  white,  tinged  with  pink,  short:  berry  large,  dark 
blue,  with  a  bloom. 

2.  VACCINIUM.      Blueberry.      Cranberry.      Bilberry.     High-bush 

Huckleberry. 

Shrubs  much  resembling  Gaylussacia,  but  the  ovary  only  4-5-celled, 
although  appearing  to  have  twice  as  many  cells  by  false  partitions:  fruit  a 
many-seeded  berry,  generally  edible.    Fruit  ripe  in  summer  and  autumn. 

V.  pennsylvanicum,  Lam.  Dwarf  early  blueberry.  Shrub,  6-20  in., 
with  smooth  green  warty  branches:  leaves  deciduous,  lance-oblong,  smooth 
and  glossy,  but  edges  serrated  and  tipped  with  little  bristly  spines:  flowers 
in  clusters,  with  corolla  cylindrical,  white  or  pink-tinged,  5-toothed;  anthers 
10,  included:  berry  many-seeded,  blue-black  with  a  bloom,  edible. 

V.  corymbosum,  Linn.  High-bush,  or  swamp,  huckleberry.  Blueberry. 
Tall  bush,  with  oblong  or  elliptical  leaves:  berries  blue,  sweet,  usually 
with  a  thick  bloom. 

V.  macrocarpon,  Ait.  Cranberry.  Creeping,  slender,  scarcely  woody: 
leaves  small,  about  J^  in.  long,  evergreen,  oval  or  oblong  and  margins 
rolled:  flowers  solitary,  on  slender  erect  pedicels,  pale  pinkish,  deeper 
colored  within,  with  4  narrow  reflexed  segments. 

3.  GAULTHERIA.    Wintergreen.    Checkerberry. 

Stems  procumbent,  with  leafy  branches  erect:  leaves  alternate,  evergreen 
and  tasting  spicy  and  aromatic:  flowers  white  or  pink,  nodding  on  axillary 
pedicels;  corolla  oblong  or  short-cylindrical  with  5  short  lobes;  anthers  10, 
awned  at  top:  fruit  berry-like,  with  capsule  inside  the  thickened  calyx. 

G.  prociimbens,  Linn.  Fig.  22.  Leaves  oval  or  obovate,  much  sought  for 
their  spicy  flavor,  as  well  as  the  edible  red,  mealy  berries,  which  last  all 
winter.    In  low  and  evergreen  woods,  6  in.  or  less  tall. 


ERICACEAE  425 

4.  EPIG^EA.    Trailing  Arbutus.    Mayflower. 

Trailing  close  to  the  ground,  with  rusty-hairy  stems,  and  alternate 
evergreen  rounded  leathery  leaves:  flowers  dimorphous,  in  clusters  at  ends 
of  branches,  bracted,  sessile;  sepals  5,  persistent  but  scale-like;  corolla  salver- 
form,  with  .r>  lobes;  stamens  10;  ovary  5-lobed. 

E.  repens,  Linn.  A  favorite  flower  of  very  early  spring,  white  to  pink, 
}  ■>  in.  broad,  spicy-scented  and  wax-like,  in  small  clusters  from  axils  of  the 
rusty  leaves.    Mostly  North. 

5.  KALMIA.    American  Latjrel. 

Shrubs,  native  (belonging  to  East  and  South),  with  entire  evergreen 
leaves:  flowers  in  umbels;  corolla  open,  saucer-like,  5-angled  with  10  little 
pits  in  which  the  anthers  of  the  10  stamens  are  caught  until  mature  or 
disturbed  by  insects,  when  the  curved  filaments  spring  upward,  discharging 
the  pollen;  style  long  and  slender. 

K.  latifolia,  Linn.  Common  mountain  laurel.  Stout  shrub,  4-20  ft., 
often  forming  great  patches  on  wild  or  rocky  hillsides;  also  cultivated: 
flowers  about  1  in.  across,  rosy,  or  white  and  red-spotted,  in  terminal  com- 
pound corymbs:  leaves  mostly  alternate,  thick,  acute,  green  on  both  sides, 
lance-ovate:  blooms  in  early  summer.    East  and  North. 

K.  angustifolia,  Linn.  Sheep  laurel.  Lambkill.  Low  shrub  with  flowers 
about  J-2  in.  across,  crimson  or  purplish,  in  lateral  corymbs:  leaves  narrow, 
obtuse,  short-pctioled,  opposite  or  in  3's,  pale  beneath.   Hillsides. 

G.  AZALEA.    Fig.  220. 

Shrubs,  with  deciduous  leaves:  flowers  showy,  in  terminal,  umbel-like 
clusters;  calyx  minute,  5-parted;  corolla  cylindrical-tubed;  stamens  usually 
5;  style  long,  slender,  exserted.  Rhododendron  is  closely  allied,  having  ever- 
green leaves,  stamens  usually  10,  stamens  and  style  usually  not  exserted. 

A.  viscosa,  Linn.  Swamp  honeysuckle.  Stems  4-10  ft.,  branching: 
leaves  obovate,  short-petioled,  mostly  smooth  above  and  downy  on  under 
veins:  flowers  in  summer  after  the  leaves,  fragrant,  white,  1-2  in.  long, 
with  slender  tubes  rather  sticky-coated,  the  tube  longer  than  the  lobes.  A 
swamp  plant. 

A.  nudiflora,  Linn.  Pinxter  flower.  Shrub,  3-6  ft.,  in  swamps:  flowers 
before  or  with  leaves,  rose-pink  or  white,  fragrant,  1-2  in.  across,  the  tube 
about  the  length  of  the  lobes. 

Rhodora  canadense,  Linn.,  or  Rhododendron  Rhodora,  Don,  of  New 
England,  is  a  low  shrub,  2-3  ft.,  with  fine  large  (1  in.  wide)  rose-colored 
flowers  appearing  before  leaves. 

7.  MONOTROPA.   Indian  Pipe.   Pine-sap. 

Low  herbs,  parasitic  on  roots  or  saprophytic,  no  green  about  them,  but 
stem  bearing  small  scales:  flowers  solitary  or  in  racemes;  sepals  2,  bract-like; 
petals  4  or  5,  erect  or  spreading,  wedge-shaped;  stamens  8-10,  hypogynous; 
anthers  kidney-shaped;  ovary  4-5-celled,  stigma  radiate  or  disk-like. 

M.    uniflora,   Linn.     Indian   pipe.     Corpse   plant.     Odd   fleshy    waxy- 


426  THE     KINDS    OF    PLANTS 

white  little  plants,  turning  black  when  drying:  stem,  3-6  in.  high,  bent 
over  at  the  top  with  one  nodding  terminal  flower. 

M.  Hypopitys,  Linn.  Pine-sap.  In  oak  and  pine  woods:  stems  scaly, 
white  or  tawny  red,  4-8  in.  high,  single  or  in  groups:  flowers  several,  small, 
rather  fragrant,  in  a  scaly  raceme. 


XLVII.  RUBIACE.E.   Madder  Family. 

A  large  and  important  family  of  herbs,  shrubs,  trees  (including 
cinchona  or  Peruvian  bark,  and  coffee):  leaves  opposite,  or  in  3's 
with  stipules  between,  or  apparently  whorled  without  stipules:  flow- 
ers perfect,  sometimes  dimorphous  (of  2  sorts)  or  trimorphous; 
calyx-tube  adherent  to  ovary,  margin  3-6-toothed;  corolla  regular, 
inserted  on  calyx-tube,  and  of  same  number  of  lobes;  stamens  of  equal 
number  as  corolla-lobes  and  alternate  with  them;  ovary  1-10- 
celled:  fruit  a  capsule,  berry  or  drupe.  A  large  family  (some  5,000 
species),  largely  tropical. 

a.  Leaves  4-8  in  a  whorl:  no  apparent  stipules:  fruit  2 

nutlets,  bur-like,  or  sometimes  berry-like 1.  Galium 

aa.  Leaves  opposite  (or  whorled),  with  stipules. 

b.  Flowers    in    pairs,    axillary:    fruit    a    double    berry: 

creeping 2.  Mitchella 

bb.  Flowers  solitary,  or  in  terminal  clusters:  not  creeping.3.  Houstonia 
bbb.  Flowers  in  round  heads 4.  Cephalanthus 

1.  GALIUM.   Cleavers.    Bedstraw. 

Frail  herbs,  with  square  stems,  often  prickly  or  rough  on  angles  and  edges 
of  leaves,  usually  diffusely  branching:  leaves  apparently  whorled  and  with- 
out stipules:  flowers  small  or  minute,  sometimes  dioecious,  in  cymes  or 
panicles,  axillary  or  terminal;  calyx  minutely  4-lobed;  corolla  3-4-lobed: 
stamens  3-^4;  ovary  2-celled:  fruit  small,  double,  dry  or  fleshy,  berry -like, 
indehiscent,  or  sometimes  with  only  1  carpel  ripening.    Many  species. 

G.  asprellum,  Michx.  Weak,  reclining,  or  nearly  erect  branching 
perennial,  the  angles  of  stems  with  backward-pointing  prickles:  leaves 
small,  not  1  in.  long,  whorled  in  4's  or  5's  on  branches,  usually  6  on  stem; 
edges  and  mid-ribs  rough  with  prickles:  flowers  tiny,  white,  numerous, 
loosely  clustered  at  end  of  branches:  fruit  small,  smooth. 

G.  circaezans,  Michx.  Wild  licorice.  Perennial,  branching,  ascending 
stems  with  leaves  in  4's,  not  prickly:  leaves  oval  to  oblong,  obtuse,  more 
or  less  pubescent,  an  inch  or  more  long:  flowers  dull  greenish  or  brownish, 
on  very  short  pedicels  in  branched  cymes;  fruit  on  reflexed  pedicels,  bristly: 
root  and  leaves  with  sweetish  taste.    Dry  woods.    Common. 

G.  Aparine,  Linn.  Cleavers.  Goose-grass.  Annual,  stems  weak,  pros- 
trate, scrambling,  and  diffuse,  with  backward-pointing  barbs  on  angles: 


RUBIACE.E  427 

small  lanceolate  leaves,  6-8  in  a  whorl,  about  1  in.  long,  rough  on  edges 
and  midrib:  peduncles  axillary,  1-3-flowered;  flowers  tiny,  white  or 
greenish:  fruit  a  dry  little  bur,  covered  with  hooked  prickles,  on  erect  pedi- 
cels.   Low  ground  or  thickety  woodland. 

2.  MITCHELLA.    Partridge-berry.    Squaw-vine. 

Trailing,  evergreen-leaved  herbs:  leaves  opposite,  round-ovate,  dark 
green,  smooth  and  glossy,  entire,  on  short  petioles:  flowers  small,  dimorphous, 
in  pairs,  on  a  double  ovary  (2  ovaries  united)  from  leaf-axils;  corolla  funnel- 
form,  4-parted,  bearded  within,  white  with  pink  tips  to  lobes;  stamens  and 
stigmas  4:  fruit  a  double  scarlet  berry,  with  4  seeds  or  stones. 

M.  repens,  Linn.  A  pretty  little  creeper  of  woods  in  the  North:  flowers 
fragrant  and  delicate,  in  June,  the  double  scarlet  berries  found  all  winter. 

3.  HOUSTONIA.    Bluets. 

Low,  delicate  little  herbs,  with  stems  erect,  simple  or  branching:  leaves 
opposite,  entire;  stipules  entire  and  short,  or  a  mere  line  connecting  bases 
of  the  opposite  leaves:  flowers  generally  dimorphous  in  respect  to  anthers 
and  stigmas,  small,  solitary  or  clustered;  calyx  4-toothed;  corolla  tubular, 
rotate,  4-lobed;  stamens  4  on  corolla:  fruit  a  short  pod,  2-celled,  many- 
seeded,  opening  at  the  top,  upper  part  free  from  calyx. 

H.  caerulea,  Linn.  Perennial,  3-6  in.,  the  stems  erect,  very  slender,  in 
tufts,  from  slender  rootstocks:  leaves  sessile,  oblong  or  spatulate,  J4_H  im 
long,  often  hairy:  flowers  blue  to  white,  with  yellow  centers,  solitary  on 
peduncle.    Early  spring  to  summer;  very  floriferous. 

4.  CEPHALANTHUS.    Button-bush. 

Shrubs  (or  small  trees):  leaves  entire,  opposite  or  verticillate:  flowers 
small  and  many,  white  or  yellow,  in  close  round  heads,  on  peduncles;  calyx 
4-toothed;  corolla  tubular,  with  4  short  lobes;  stamens  4  on  corolla  throat; 
style  long  and  exserted:  fruit  small,  dry,  inversely  pyramidal. 

C.  occidentalis,  Linn.  Tall  shrub  with  leaves  in  2's  or  3's,  oval-pointed, 
petioled,  with  stipules  between:  heads  of  whitish  flowers  about  1  in.  in 
diameter.    Usually  along  streams  and  pond  banks. 


XLVIII.  CAPRIFOLIACE.E.   Honeysuckle  Family. 

Erect  or  twining  shrubs,  or  sometimes  herbs,  with  opposite  mostly- 
simple  leaves:  flowers  epigynous,  5-merous,  regular  or  irregular, 
tubular  or  rotate;  stamens  usually  as  many  as  the  lobes  of  the  corolla 
and  inserted  on  its  tube;  ovary  2-5-loculed,  ripening  into  a  berry, 
drupe,  or  capsule.  About  15  genera  and  200  species.  Characteristic  plants 
are  honeysuckle,  elder,  viburnum,  snowberry,  weigela,  twin-flower. 

a.  Corolla  long-tubular. 

b.  Fruit  a  berry  (often    2   together)    several-seeded:   leaf- 
margins  entire  or  wavy  edged:  sometimes  connate 1.  Lonicera 


428  THE    KINDS    OF    PLANTS 

bb.  Fruit  a  linear-oblong  capsule,   2-valved,  many-seeded: 

leaf -margin  serrate 2.  Diervilla 

aa.  Corolla  shallow,  usually  rotate. 

b.  Leaves  simple 3.  Viburnum 

bb.  Leaves  pinnately  compound 4.  Sambucus 

1.  LONICERA.   Honeysuckle. 

Erect  or  twining  shrubs,  with  tubular,  funnelform,  more  or  less  irregular 
flowers  (often  2-lipped);  corolla  bulging  oh  one  side  near  the  base;  stamens 
5:  fruit  a  berry,  usually  2  together  from  2  contiguous  flowers. 

a.  Erect. 

L.  canadensis,  Marsh.  Open,  smooth  bush,  3-5  ft.:  leaves  cordate- 
oblong,  not  sharp-pointed,  entire:  flowers  less  than  1  in.  long,  soft  yellow, 
the  lobes  nearly  equal:  berries  red.  Common  in  woods.  Blooms  in  very 
early  spring. 

L.  tatarica,  Linn.  Tartarian  honeysuckle.  Tall  shrub  (to  12  ft.): 
leaves  cordate-oval,  not  long-pointed,  entire:  flowers  pink  or  red  (some- 
times nearly  white),  2-lipped,  all  the  lobes  oblong.  Asia,  but  common 
in  yards.    Spring. 

aa.  Twining. 

L.  japonica,  Thunb.  (L.  Halliana  of  gardens).  Fig.  554.  Weak  twiner, 
with  oblong  or  ovate  entire  nearly  evergreen  leaves:  flowers  small,  on  short 
pedicels,  fragrant,  opening  white  or  blush  but  changing  to  yellow.  Japan; 
much  cultivated. 

L.  Periclymenum,  Linn.    Probably  the  commonest  of  the  old-fashioned 
climbing  honeysuckles  (from  Old  World);  strong  and  woody:  leaves  oblong- 
ovate,  not  joined  by  their  bases,  entire,  dark  green  above  and  pale  beneath: 
flowers  large,  reddish  outside  and  yellow  inside,  very  fragrant,  in  a  dense, 
i  long-stalked  cluster. 

L.    sempervirens,    Ait. 
jt'if^f       /  Trumpet    or    coral     honey- 

suckle. Fig.  148.  Glabrous 
twining  shrub,  with  leaves 
evergreen,  oblong,  entire, 
glaucous,  upper  pairs  joined 
at  base  about  the  stem, 
appearing  perfoliate:  flowers 
nearly  sessile,  in  rather 
Lonicera  Japonioa.  f^       distant  whorled  clusters  on 

terminal  spikes,  the  corolla 
trumpet-shape,  tube  almost  regularly  5-lobed,  1^-2  in.  long,  scarlet  without, 
yellowish  within;  stamens  and  style  not  much,  if  any  projecting.  Moist  or 
low  ground,  often  cultivated. 


CAPRIFOLIACE.E  429 

2.  DIERVILLA.    Bush  Honeysuckle. 

Erect,  low  shrubs  or  bushes:  leaves  simple,  opposite,  ovate  or  oblong, 
acute-pointed,  serrate,  deciduous:  flowers  in  axillary  or  terminal  cymes,  or 
solitary;  calyx-tube  slender,  limb  of  5  slender,  persistent  lobes;  corolla 
funnelform,  5  lobes  almost  regular;  stamens  ">;  ovary  inferior,  2-celled, 
1  filiform  style:  fruit  slender  2-celled  many-seeded  pod,  crowned  with  calyx. 

D.  Lonicera,  Mill.  Busby  shrub,  1-4  ft.:  leaves  oval  to  ovate,  taper- 
pointed,  on  short  petioles:  peduncles  terminal  or  in  upper  axils,  mostly  3- 
flowered:  corolla  slender,  tubular,  greenish  yellow  (honey  color),  not  over 
:(4  in.  long.    Hanks.    Summer. 

D.  hybrida,  Hort.  Weigela.  Shrub,  2-8  ft.:  leaves  oval,  acute  coarsely 
senate,  rather  rough  above  and  soft  below,  short-petioled :  flowers  funnel- 
form,  1-1 J  2  in.  long;  tube  downy  without;  5-lobed;  the  limb  spreading.  A 
group  of  common  garden  shrubs,  derived  from  2  or  more  Japanese  species, 
with  white,  pink,  or  red  showy  flowers. 

3.  VIBURNUM.    Arrow-wood. 

Erect  shrubs,  with  simple  leaves  and  small  whitish  flowers  in  broad 
cymes:  stamens  5;  stigmas  1-3:  fruit  a  small  1-seeded  drupe. 

a.  Flowers  all  alike  in  the  cyme. 

V.  Lentago,  Linn.  Sheepberry.  Fig.  305.  Tall  shrub  (to  20  ft.):  leaves 
ovate-pointed,  finely  and  sharply  serrate,  shining  above,  on  long  margined 
petioles:  fruit  l  ■>  in.  or  more  long,  black.    Common. 

V.  acerfolium,  Linn.  Dockmackir.  Arrow-wood.  Six  ft.  or  less:  leaves 
3-lobed  and  maple-like,  downy  beneath:  cyme  small  and  slender-stalked: 
fruit  flat  and  small.    Woods. 

aa.  Flowers  larger  on  the  margin  of  the  cyme. 

V.  6pulus,  Linn.,  var.  americanum,  Ait.  High-bush  cranberry.  Erect, 
10  ft.  or  less:  leaves  3-lobed  and  toothed:  outer  flowers  sterile  and  large: 
fruit  an  acid  red  edible  drupe.  Swamps.  In  cultivation  all  the  flowers  have 
become  sterile,  resulting  in  the  "snowball."    Compare  Figs.  264,  265. 

V.  tomentosum,  Thunb.  (V.  plicatum  of  gardens).  Japanese  snowball. 
Leaves  not  lobed,  shallow-toothed,  thickish,  plicate:  heads  of  sterile  flowers 
axillary,  globular.   Japan. 

V.  alnifolium,  Marsh.  Hohblebush.  About  5  ft.,  with  straggling  branches, 
often  arching  to  ground  and  rooting,  thus  making  loops  or  "hobbles:" 
flowers  resemble  those  of  wild  hydrangea,  in  flat-topped  cymes,  with  mar- 
ginal flowers  larger,  sterile  and  showy,  white:  leaves  very  large,  round  or 
heart-shaped,  finely  serrate,  petioles  and  veinlets  scurfy:  drupes  coral-red, 
becoming  purple,  not  edible.    Cold  woods  and  swamps. 

4.  SAMBtTCUS.    Elder. 

Strong  shrubs,  with  pinnate  leaves  and  sharp-serrate  leaflets:  flowers  in 
dense  corymbose  cymes;  calyx-teeth  very  small  or  none;  corolla  shallow, 
open ;  stamens  5 ;  stigmas  3 :  pith  prominent  in  the  stems.   Common. 


430  THE    KINDS    OF    PLANTS 

S.  racemosa,  Linn.  Red  elder.  Pith  and  berries  red:  flowers  in  spring 
in  pyramidal  clusters:  leaflets  lanceolate,  downy  beneath. 

S.  canadensis,  Linn.  Common  elder.  White  elder.  Pith  white:  berries 
black-purple,  in  late  summer,  edible:  flower-clusters  convex  or  nearly  flat, 
in  summer:  leaflets  oblong,  smooth. 


XLIX.  CAMPANULACEjE.   Bellflower  Family. 

Herbs  (with  us):  leaves  alternate,  simple,  without  stipules:  flow- 
ers regular  and  perfect,  mostly  bell-shaped  corollas,  5-lobed  or  5- 
angled;  calyx  5-lobed;  stamens  5,  distinct;  ovary  2-5-celled;  style  1; 
stigmas  2-5:  fruit  a  capsule.   Some  1,200  or  more  species. 

a.  Corolla   (of  the  conspicuous  flowers)  wheel-shape:  early 

flowers  not  opening  (cleistogamous) 1.  Specularia 

aa.  Corolla  bell-form:  flowers  all  alike 2.  Campanula 

1.  SPECULARIA. 

Annual  herbs,  with  erect,  angled  stems,  simple  or  branching:  leaves 
entire  or  toothed:  flowers  sessile  or  nearly  so,  axillary,  solitary  or  clustered, 
the  early  ones  cleistogamous  and  small,  the  later  expanding,  light  blue, 
5-lobed,  wheel-shaped  corolla;  filaments  shorter  than  the  anthers. 

S.  perfoliata,  DC.  Stems  erect,  simple  or  branched,  10  in.  to  3  ft.  tall, 
leafy,  the  leaves  rounded  heart-shaped  or  broadly  ovate,  with  clasping  bases: 
flowers  solitary,  2  or  3  together  in  leaf-axils.    More  or  less  weedy. 

S.  Speculum,  DC.  Venus'  looking-glass.  Low  garden  annual,  with  stem 
branching  diffusely:  flowers  purplish  lilac  to  rose-colored  or  white,  solitary 
and  terminal:  leaves  oblong,   crenate. 

2.  CAMPANULA.    Bellflower.    Harebell. 

Flowers  solitary  or  racemed  or  spiked,  blue  or  white,  not  cleistogamous: 
calyx  5-lobed;  corolla  bell-shaped:  pod  roundish,  opening  at  sides  (Fig.  283). 

C.  aparinoides,  Pursh.  A  weak,  reclining,  Galium-like  perennial,  found 
among  grasses  in  moist  meadows:  stem  very  slender,  triangular,  angles 
bearing  rough  backward-pointing  prickles:  leaves  small,  lance-linear,  entire: 
flowers  very  small,  about  l/i  in.  long,  white,  on  spreading  pedicels. 

C.  rotundifolia,  Linn.  Common  harebell.  Perennial  from  slender  root- 
stocks,  nearly  or  quite  glabrous,  5-12  in.  high:  root-leaves  rounded  or 
cordate,  often  withering  before  blooming  season,  the  stem-leaves  linear  to 
narrow-lanceolate,  entire:  flowers  few  or  solitary  on  slender  pedicels,  nod- 
ding when  open;  corolla  bell-shaped,  with  pointed  lobes,  Y^-Yz  in.  long,  blue. 
Rocky  places,  northward. 

C.  Medium,  Linn.  Canterbury  bell.  Cultivated  from  Europe,  annual 
or  biennial,  erect  to  3  ft.,  rather  hairy,  branching  or  simple:  leaves  lanceo- 
late, rather  coarsely-toothed:  flowers  2-3  in.  long,  single  or  double,  blue; 
stigmas  5;  sepals  leafy-appendaged  at  base. 


LOBELIACE.E — COMPOSITE  431 

L.  LOBELIACEjE.   Lobelia  Family. 

Herbs:  leaves  alternate  or  radical,  simple:  flowers  scattered, 
racemed  or  panicled,  often  leaf y-bracted ;  calyx-tube  adherent  to 
ovary;  corolla  irregular,  monopetalous,  5-lobed,  usually  split  on  one 
side;  stamens  5,  usually  united,  at  least  by  anthers,  about  the  1 
style;  stigma  2-lobed:  fruit  a  capsule,  loculicidally  2-valved. 

LOBELIA. 

Flowers  often  showy,  axillary  and  solitary,  or  in  terminal  bracted 
racemes;  corolla  as  if  2-lipped;  stamens  generally  unequal,  monadelphous,  2 
or  all  of  the  5  anthers  bearded  at  the  top.    Many  species. 

L.  cardinalis,  Linn.  Cardinal  flower.  Indian  pink.  A  showy  plant 
of  swampy  or  moist  soil,  also  cultivated:  tall,  simple  stem,  2-4  ft.,  with 
showy,  deep-red  flowers  (rarely  pale  colored),  about  1  in.  long,  bracted,  in 
terminal  racemes:  leaves  sessile,  lance-oblong,  slightly  toothed. 

L.  Erinus,  Linn.  The  common,  pretty,  annual  trailing  or  spreading 
Lobelia  of  gardens  and  greenhouses:  flowers  many,  small,  very  blue,  usually 
with  white  throats  (varying  to  whitish):  lower  leaves  spatulate;  upper 
narrow,  toothed. 

L.  syphilitica,  Linn.  Stem  erect  to  1-3  ft.,  angular,  heavy:  leaves 
oblong-ovate,  irregularly  serrate:  flowers  in  terminal,  leafy  raceme;  flowers 
intense  blue  (or  white),  1  in.  or  more  long;  calyx  hairy  or  hispid,  lobes 
auricled  at  base,  dentate.  Perennial,  in  low  or  marshy  grounds  or  along 
streams.    Late  summer. 

L.  spicata,  Lam.  Erect  smoothish  stems,  1-3  ft.,  sparingly  leafy,  the 
terminal  raceme  with  linear,  small  bracts:  leaves  oblong,  upper  small  and 
narrow:  flowers  small,  pale  blue;  calyx-lobes  not  auricled  at  base,  entire. 
Dry,  sandy  soil. 

L.  infiata,  Linn.  Indian  tobacco.  Erect,  9-12  in.,  rather  hairy,  branch- 
ing: leaves  ovate,  toothed:  flowers  small,  H  in.  long,  pale  blue,  in  loose, 
racemes,  leafy-bracted:  capsules  inflated,  large.  Common  in  fields^  juice 
pungent-poisonous. 

LI.  COMPOSITE.   Composite  or  Sunflower  Family. 

Mostly  herbs,  many  of  them  very  large,  very  various  in  foliage: 
flowers  small,  densely  packed  into  an  involucrate  head,  5-merous; 
the  corolla  of  the  outer  ones  often  developed  into  long  rays;  stamens 
5,  the  anthers  united  around  the  2  styles:  fruit  dry  and  1-seeded, 
indehiscent,  usually  crowned  with  a  pappus  which  represents  a  calyx. 
The  largest  of  all  phenogamous  families,  comprising  about  one-tenth 
of  all  flowering  plants, — about  800  genera  and  11,000-12,000  species. 
Common  composites  are  sunflower,  aster,  goldenrod,  boneset,  dahlia, 
chrysanthemum,  marigold,  compass  plant,  thistles,  dandelion,  lettuce. 


432 


THE     KINDS    OF    PLANTS 


a.  Heads  with  all  flowers  strap-shaped  (with  rays)  and 
perfect:  juice  milky:  leaves  alternate. 
b.  Flower-heads  terminal    on  leafless,   hollow  stalk 

from  radical  leaves 1.  Taraxacum 

bb.  Flower-heads    terminal    on    leafy    stalks:    leaves 

parallel-veined 2.  Tragopogon 

bbb.  Flower-heads  in  corymbs  or  clusters. 

c.  Heads  never  yellow    (usually   blue  or  white): 

pappus  of  blunt  scales 3.  Cichorium 

cc.  Heads  usually  yellow  (in  one  case  blue). 

d.  Achenes  beaked:  pappus  copious,  white,  soft, 
hair-like:  leaves  sometimes  bristly  or  prickly 

edged 4.  Lactuca 

dd.  Achenes  not  beaked. 

e.  Pappus    soft,   white:    leaves    usually  auri- 
cled   and    clasping  at    base,   and   prickly 

on  edges  and  under  ribs 5.  Sonchus 

ee.  Pappus  stiff,  brownish,  leaves  not  spiny. . .   6.  Hieracium 
va.  Heads  with  tubular  and  mostly  perfect  disk  flowers, 
the  rays,  if  any,  formed  of  the  outer  strap-shaped 
and   imperfect   flowers:   in   cultivated   species,   all 
the     flowers     may     become     strap-shaped     (head 
"double"):  juice  not  milky. 
B.  Fruit  a  completely  closed  and  bur-like  involucre, 
containing    1    or    2    small  achenes:  flowers  im- 
perfect (see  also  No.  23). 

c.   Involucre-bur  large,  and  sharp-spiny 7.  Xanthium 

cc.  Involucre-bur  small,  not  sharp-spiny 8.  Ambrosia 

bb.  Fruit  not  formed  of  a  closed  and  hardened  in- 
volucre  (although  the  involucre  may  be  spiny, 
as  in  Arctium  and  Cnicus). 
c.  Pappus  none:  achenes  not  awned. 
d.  The  leaves  opposite. 

e.  Leaves  simple:  flower-heads  small:  flowers 

blue  or  white 9.  Ageralum 

ee.  Leaves     compound:     flower-heads     large, 

various  colors,  mostly  of  ray  florets 10.  Dahlia 

eee.  Leaves  dissected:  heads  showy 11.  Cosmos 

eeee.  Leaves    various:    rays    usually    about    8, 

neutral  and  yellow.    (See  Coreopsis,  21.) 
dd.  The  leaves  alternate. 
E.  Foliage  finely  divided. 

f.  Heads   small    (about    }4   in.):    achenes 

flattened 12.  Achillea 

FF.  Heads  good-sized  (about  1   in.):  achenes 

oblong,  angled  or  ribbed 13.  Anthemis 


COMPOSITES  433 

ee.  Foliage  leaves  entire,   toothed,   or  broad- 
lobed. 
F.  Achenes  curved  or  horse-shoe-shaped.. . .  14.  Calendula 
ff.  Achenes  straight. 

g.  Torus  flat  or  slightly  convex 15.  Chrysanthemum 

GG.  Torus  conical. 

h.  Rays  yellow:  Sowers  large,  2-3  in.. .16.  Rudbeckia 
nu.  Rays    not    yellow:    flowers    about 

1  in.  across:  plant  low 17.  Bellis 

cc.  Pappus  of  2  thin  early  deciduous  scales 18.  Helianthus 

ccc.  Pappus  a  short  crown,  or  achenes  awned  at  the 
top  with  (2  or  more)  awns. 
d.   Achenes  angled  or  ribbed,  crowned  with  cup- 
like   or    lobed    pappus:     foliage    strongly 

"tansy"  scented 19.  Tanacetum 

dd.  Achenes   more   or  less  flattened,   and  awned 
at  summit,  with  usually  2  or  4  awns. 
e.  Awns   barbed  downward:   achenes  various, 
narrowed    at    top,    and    awned,    but    not 

really  beaked 20.  Bidens 

ee.  Teeth    not    downwardly    barbed:     (some- 
times achenes  awnless. ) 21.  Coreopsis 

cccc.  Pappus  of  many  bristles. 

d.  Plant  very  prickly 22.   Cirsium 

dd.   Plant  not  prickly. 

e.   Involucre  prickly  and  bur-like 23.  Arctium. 

ee.  Involucre  not  bur-like  or  prickly. 

F.  Torus   bristly    (chaff  or   bracts   amongst 

the  florets) 24.  Centaurea 

ff.   Torus  naked. 
g.   Rays  present. 
h.  Flowers  yellow. 

i.  Leaves  all  radical:  rays  numerous 

and  fertile 25.  Tussilago 

ii.  Leaves  on  stems,  alternate. 

J.  Heads   small,    in    large    clusters 

or  panicles 26.  Solidago 

jj.  Heads  large  and  broad:  leaves 
large  on  stem  and  in  a  basal 

clump 27.  Inula 

HH.   Flowers  not  yellow. 

I.  Scales  of  the  involucre  unequal. .  .28.  Aster 

ii.  Scales  equal  in  length 29.  Erigeron 

in.  Scales   in   several    rows,    more   or 

less  leafy 30.  Callistephus 

gg.  Rays  none. 


434  THE    KINDS    OF    PLANTS 

h.  Plants    cottony-white,    or    downy- 
looking. 
i    Heads  mostly  dicecious. 

J.  Leaves  basal  and  also  on  stem: 
pappus  thickened  at  summit 
and  more  or  less   barbed   or 

plumed 31.  Antennaria 

jj.  Stems  leafy:  pappus  not  thick- 
ened at  summit:  some  sterile 
flowers,    usually   in   center   of 

the  fertile  heads 32.  Anaphahs 

II.  Heads  not  dicecious:  outer  flowers 

pistillate,  central  perfect 33.  Gnaphalium 

hh.  Plants  not  cottony-white. 

I.  Flower-heads    showy,     spicate    or 
racemed,      rose-purple:      leaves 

alternate 34.  Liatris 

ii.  Flower-heads  small,   in   cymes  or 
corymbs, 
j.  Flowers   white   or   pale   purple: 

leaves  mostly  opposite 35.  Eupatorium 

jj.  Flowers  purple:  leaves  alter- 
nate   36.  Vernonia 

1.  TARAXACUM.    Dandelion. 

Stemless  herbs,  the  1-headed  scape  short,  leafless  and  hollow:  florets 
all  perfect  and  strap-shaped:  fruit  ribbed,  the  pappus  raised  on  a  long  beak. 
Variable  plants. 

T.  officinale,  Weber  (T.  Dens-leonis,  Desf.).  Common  dandelion.  Figs. 
8,  302.  Perennial,  introduced  from  the  Old  World:  leaves  long,  pinnate  or 
lyrate:  heads  yellow,  opening  in  sun. 

2.  TRAGOPOGON.    Goat's  Beard. 

Biennials  or  perennials,  stout,  smooth,  often  glaucous,  with  long,  grass- 
like  leaves  clasping  the  stem:  flowers  all  ligulate,  in  large  solitary  heads, 
purple  or  yellow,  terminal  on  long  peduncle,  with  single  involucre  of  many 
bracts,  which  are  equal  and  lanceolate,  joined  at  bases:  pappus  in  one 
series,  long  and  plumose:  achenes  linear,  mostly  with  long  slender  beaks, 
5-10-ribbed  or  angled:  flowers  open  in  early  morning,  usually  closed  at 
midday.    Juice  milky. 

T.  porrifolius,  Linn.  Salsify.  Oyster-plant.  Biennial;  involucral  bracts 
much  longer  than  the  rays:  stems  2-3  ft.  high,  hollow  and  thickened 
upward:  flowers  purple.  Europe.  Cultivated  for  the  edible  tap-root.  Some- 
times wild. 

T.  pratensis,  Linn.  Similar  to  preceding,  but  flowers  yellow  and  in- 
volucral bracts  not  longer  than  rays.  Europe.  Fields  and  waste  places, 
eastern  and  middle  states. 


COMPOSITES  435 

3.  CICHORIUM.   Chicory. 

Tall,  branching  perennials,  with  deep,  hard  roots:  florets  perfect  and 
strap-shaped:  fruit  lightly  grooved,  with  sessile  pappus  of  many  small, 
chaffy  scales. 

C.  Intybus,  Linn.  Common  chicory.  Runs  wild  along  roadsides  (from 
Europe);  2-3  ft.:  leaves  oblong  or  lanceolate,  the  lowest  pinnatifid:  flowers 
bright  blue  or  pink,  2-3  together  in  the  axils  on  long  nearly  naked  branches. 

4.  LACTtTCA.    Lettuce. 

Coarse  weedy  plants:  stems  tall  and  leafy,  simple  or  branching,  car- 
rying small  panicled  heads  of  insignificant  flowers:  juice  milky:  stem-leaves 
alternate,  entire,  or  pinnately  divided  with  lobes  and  margins  and  under 
midrib  often  spine-tipped:  involucre  cylindrical,  with  bracts  in  2  or  more 
unequal  rows;  flowers  all  ligulate  and  perfect,  with  the  ligules  truncate  and 
5-toothed:  achenes  oval  to  linear,  flattened,  3-5-ribbed  on  each  face, 
smooth,  abruptly  narrowed  into  a  beak:  pappus  abundant,  white  or  brown- 
ish and  soft. 

L.  canadensis,  Linn.  Common  in  rich  soil,  3-9  ft.  tall:  leaves  smooth, 
lanceolate  to  spatulate,  sessile  or  clasping,  margins  entire,  sinuate,  or 
runcinately  pinnatifid,  the  radical  leaves  petiolate — all  smooth  and  glaucous; 
flowers  pale  yellow,  in  small  heads  (K~M  m-  long),  the  heads  more  or  less 
diffusely  panicled.    Biennial  or  annual. 

L.  villosa,  Jacq.  Three  to  8  ft. :  leaves  ovate  to  lanceolate,  pointed  and 
serrate,  teeth  mucronate,  sometimes  hairy  on  under  midrib,  the  petioles 
winged,  more  or  less  sinuate  or  clasping  and  arrow-shaped:  inflorescence  a 
panicle  of  numerous  small  heads;  rays  bluish:  achenes  short-beaked  or 
beakless:  pappus  brownish.    Biennial  or  annual. 

L.  Scariola,  Linn.  Prickly  lettuce.  Fig.  86.  Glabrous  and  rather  glaucous- 
green,  with  tall,  stiff,  erect  stem,  branching,  usually  somewhat  prickly: 
leaves  oblong  or  spatulate,  dentate  or  pinnatifid,  sessile,  or  auricled  and 
clasping,  with  margins  and  under  midrib  spiny:  heads  small,  6-12-flowered, 
but  numerous,  the  rays  yellow;  involucre  narrow,  cylindric:  achenes  flat, 
ovate-oblong,  with  long  filiform  beak.  Europe.  A  common  coarse  biennial 
weed. 

L.  sativa,  Linn.  Garden  lettuce.  Cultivated  for  the  tender  root-leaves 
as  a  salad:  flowers  yellow  on  tall  small-leaved  stems. 

5.  SONCHUS.   Sow  Thistle.    Milk  Thistle. 

Coarse,  succulent  weeds,  smooth  and  glaucous  or  spiny,  with  leafy  stem, 
resembling  wild  lettuce,  but  achenes  truncate,  not  beaked,  and  the  flowers 
always  yellow:  involucre  bell-shape  in  several  unequal  series;  rays  truncate, 
5-toothed.    All  from  Europe. 

S.  oleraceus,  Linn.  Annual,  from  fibrous  roots,  1-5  ft.,  with  pale  yellow 
flowers  in  heads  %-l  in.  in  diameter:  leaves  various,  mostly  on  lower  part 
of  stem,  petiolate  or  clasping  by  an  auricled  base,  the  lobes  acute;  in  shape 
lanceolate  to  lyrate-pinnatifid,  margins  spinulous. 

S.  arvensis,  Linn.    Perennial  with  creeping  rootstocks:  flowers  bright 


436 


THE    KINDS    OF    PLANTS 


555.    Xanthium 
canadenae. 


yellow  in  showy  heads:  leaves  various,  but  spiny  on  margins,  and  generally 
with  clasping,  auricled  bases:  bracts  of  the  involucre  bristly. 

S.   asper,  Hill.     Spiny-leaved  sow  thistle.    Annual  weed:  resembles  S. 
oleraceus  closely,  but  the  clasping  auricles  are  rounded  at  base,  stem-leaves 
not  so  divided  and  more  spiny. 

6.  HIERACIUM.    Hawkweed. 

Hairy,  or  glandular-hispid,  or  glabrous  perennials, 
with  radical  or  alternate  entire  leaves:  head  of  12-20 
yellow  or  orange  ligulate  flowers,  solitary  or  panicled; 
involucre  in  one  or  several  series,  unequal;  rays  trun- 
cate and  5-toothed:  achenes  oblong,  striate,  not 
beaked;  pappus  single  or  double,  delicate,  tawny  or 
brownish,  stiff,  not  plumose.  Large  number  of  species 
widely  spread. 

H.  venosum,  Linn.  Rattlesnake-weed.  Smooth, 
slender,  leafless  or  with  1  or  few  leaves,  1-2  ft.,  fork- 
ing into  a  loose,  spreading  corymb  of  heads:  leaves  thin,  glaucous,  radical 
and  tufted,  or  near  base  on  stem,  oblong  or  oval,  nearly  entire,  slightly 
petioled  or  sessile,  sometimes  purplish  or  marked  with  purple  veins:  achenes 
linear,  not  narrowing  upward.    Dry  woods. 

H.  aurantiacum,  Linn.  Orange  hawkweed.  Devil's  paint-brush.  A  very 
bad  weed  in  meadows  East,  from  Europe:  hirsute  and  glandular:  leaves 
narrow:  heads  deep  orange:  achenes  oblong,  blunt. 

7.  XANTHIUM.    Clotbur. 

Coarse  homely  annual  weeds  with  large  alternate  leaves:  flowers  mon- 
oecious: in  small  involucres;  sterile  involucres  composed  of  separate  scales, 
in  short  racemes;  fertile  involucres  of  united  scales  forming  a  closed  body, 
clustered  in  the  leaf-axils,  becoming  spiny  burs. 

X.  canadense,  Mill.  Common  clotbur.  Fig.  555. 
One  to  2  ft.,  branching:  leaves  broad-ovate,  petioled, 
lobed  and  toothed:  burs  oblong-conical,  1  in.  long, 
with  2  beaks.    Waste  places. 

X.  spinosum,  Linn.  Spiny  clotbur.  Pubescent,  with 
3  spines  at  the  base  of  each  leaf:  bur  M  in.  long,  with 
1  beak.    Tropical  America. 

8.  AMBROSIA.    Ragweed. 

Homely  strong-smelling  weeds,  monoecious:  sterile 
involucres  in  racemes  on  the  ends  of  the  branches,  the 
scales  united  into  a  cup;  fertile  involucres  clustered  in 
the  axils  of  leaves  or  bracts,  containing  1  pistil,  with 
4-8  horns  or  projections  near  the  top.  Following  are 
annuals: 

A.  artemisiaefolia,  Linn.  Common  ragweed.  Figs. 
416,  556.    One  to  3  ft.,  yery  branchy;  leaves  opposite 


556.    Ambrosia  arte- 
misiaefolia. 


COMPOSITES  437 

or  alternate,  thin,  once-  or  twice-pinnatifid:  fruit  or  bur  globular,  with  0 
spines.    Roadsides  and  waste  places. 

A.  trifida,  Linn.  Great  ragweed.  Three  to  12  ft.,  with  opposite  3-lobed 
serrate  leaves:  fruit  or  bur  obovate,  with  5  or  6  tubercles.    Swales. 

9.  AGERATUM.    Ageratum. 

Small  diffuse  mostly  hairy  herbs,  with  opposite  simple  leaves:  heads 
small,  blue,  white  or  rose,  rayless,  the  involucre  cup-shaped  and  composed 
of  narrow  bracts;  torus  flattish;  pappus  of  a  few  rough  bristles. 

A.  conyzoides,  Linn.  (A.  mexichnum  of  gardens).  Annual  pubescent 
herb,  with  ovate-deltoid  serrate  leaves:  cultivated  (from  tropical  America) 
for  small  and  numerous  clustered  soft  heads. 

10.  DAHLIA. 

Stout  familiar  garden  herbs,  tall  and  branching,  from  tuberous  roots: 
leaves  opposite,  pinnately  divided:  ray  flowers  in  natural  state  are  neutral 
or  pistillate  and  fertile;  disk  flowers  perfect;  involucre  double,  outer  scales 
distinct  and  leaf-like,  the  inner  united  at  base;  receptacle  chaffy;  pappus 
none.    In  the  big  cultivated  dahlias,  most  of  the  flowers  are  rays. 

D.  variabilis,  Desf.  Figs.  257,  258.  Several  feet,  with  fine  large  heads 
of  flowers,  colors  various;  heads  solitary:  leaves  pinnate,  leaflets  unequal, 
3-7,  ovate-acuminate,  coarsely  serrate.    Mexico. 

11.  C6SMOS. 

Handsome  tall  plants,  4-5  ft.  high,  cultivated  for  the  fine  foliage  and  late 
flowers:  leaves  opposite,  very  finely  dissected,  thrice-compound,  the  leaflets 
extremely  narrow,  and  sessile:  flower-head  with  double  involucre;  the  outer 
bracts  dark  green,  calyx-like,  8  in  number,  the  inner  scales  erect,  with 
recurved  tips;  ray  flowers,  usually  8,  neutral,  white,  pink;  disk  flowers  per- 
fect, tubular,  yellow;  receptacle  chaffy:  achenes  flattened,  beaked.    Mexico. 

C.  bipinnatus,  Cav.  Rays  1-2  in.  long,  crimson,  rose  or  white,  the  disk 
yellow.    The  commonest  species. 

C.  sulphureus,  Cav.    Both  rays  and  disk  yellow. 

12.  ACHILLEA.    Yarrow. 

Low  perennial  or  annual  herbs:  heads  corymbose,  many-flowered,  white 
or  rose,  with  fertile  rays;  scales  of  involucre  overlapping  (imbricated) ;  torus 
flattish,  chaffy;  pappus  none. 

A.  Millefolium,  Linn.  Yarrow.  Stems  simple  below,  but  branching  at 
the  top  into  a  large  rather  dense  umbel-like  flower-cluster:  leaves  very 
dark  green,  twice  pinnatifid  into  very  fine  divisions:  rays  4-5.  Fields 
everywhere. 

13.  ANTHEMIS.    Chamomile.    Fig.  417. 

Strong-scented,  branching  herbs  with  finely  pinnatifid  leaves  and 
many-flowered  heads,  solitary  on  peduncles:  ray  flowers  white  or  yellow, 
pistillate  or  neutral,  the  edge  of  corolla  entire  or  "2-3-toothed:  disk  flowers 


438 


THE    KINDS    OF    PLANTS 


perfect,  fertile,  yellow,  corolla  5-cleft;  receptacle  convex,  partially  chaffy; 
involucral  bracts  small,  dry,  in  several  series,  outermost  shortest:  achenes 
round  or  ribbed,  smooth:  pappus  none  or  a  slight  border.  There  are  a 
number  of  cultivated  plants  in  this  genus. 

A.  Cotula,  DC.  May-weed.  Annual,  bushy,  erect,  1-2  ft.:  heads  ter- 
minal, corymbed,  1  in.  broad;  rays  usually  white,  neutral;  disk  flowers  yel- 
low: leaves  alternate,  mostly  sessile,  finely  pinnatifid.    Roadsides.   Europe. 

14.  CALENDULA.    Pot  Marigold. 

Erect,  quick-growing  annuals,  with  terminal  large  yellow  or  orange  heads 
with  pistillate  rays:  involucre  of  many  short  green  scales;  torus  fiat;  pap- 
pus none:  achenes  of  the  ray  florets  (those  of  the  disk  florets  do  not  mature) 
curved  or  coiled. 

C.  officinalis,  Linn.  Common  pot  marigold.  A  common  garden  annual 
from  the  Old  World,  with  alternate  entire  sessile  oblong  leaves:  1-2  ft. 


15.  CHRYSANTHEMUM.   Chrysanthemum. 

Erect  herbs,  annual  or  perennial,  with  alternate  lobed  or  divided  leaves: 
rays  numerous,  pistillate  and  ripening  seeds;  torus  usually  naked,  flat  or 
convex;  pappus  none. 

a.  Achenes  of  ray  florets  winged. 

C.  morifolium,  Ram.  (C.  sinense,  Sabine).  Greenhouse 
chrysanthemum.  Tall  and  mostly  strict,  with  lobed,  firm  and 
long-petioled  alternate  leaves:  flowers  exceedingly  various. 
China. 

aa.   Achenes  not  winged. 

C.  Leucanthemum,  Linn.  Whiteweed.  Ox-eye  daisy.  Fig. 
189.  Perennial,  with  many  simple  stems  from  each  root,  rising 
1-2  ft.,  and  bearing  alternate  oblong  sessile  pinnatifid  leaves: 
heads  terminating  the  stems,  with  long  white  rays  and  yellow 
disks.     Fields  everywhere  in  the  East,  and  spreading  West. 

16.  RUDBECKIA.   Cone-flower. 
beck'    hh-ta  Perennial    or   biennial    herbs,  with    alternate  leaves  and 

showy  yellow-rayed  terminal  heads :  ray  florets  neutral ;  scales 
of  involucre  in  about  2  rows,  leafy  and  spreading;  torus  long  or  conical,  with 
a  bract  behind  each  floret:  achenes  3-angled,  with  no  prominent  pappus. 
Strong  field  plants. 

R.  hirta,  Linn.  Black-eyed  Susan.  Ox-eyed  daisy  in  the  East.  Fig.  557. 
Biennial,  1-2  ft.,  coarse-hairy,  leaves  oblong  or  oblanceolate,  nearly  entire, 
3-nerved:  rays  as  long  as  the  involucre  or  longer,  yellow,  the  disk  brown; 
torus  conical.    Dry  fields. 

R.  laciniata,  Linn.  Two  to  7  ft.,  perennial,  smooth,  branching:  leaves 
pinnate,  with  5-7-lobed  leaflets,  or  the  upper  ones  3-5-parted:  rays  1-2  in. 
long;  torus  becoming  columnar.    Low  places. 


COMPOSITES  439 

17.  b£LLIS.    Garden  Daisy. 

Low  tufted  herbs  with  many-flowered  heads,  solitary  on  scapes:  leaves 
spatulate,  petioled:  flowers  both  radiate  and  tubular,  mostly  double,  with 
margins  of  the  rays  various,  quilled,  and  otherwise  modified  in  the  cul- 
tivated forms:  ray  flowers  white  or  pink,  pistillate;  disk  flowers  yellow, 
perfect  with  tubular  corolla,  limb  4-5-toothed:  achenes  flattened,  wingless, 
nerved  near  margins. 

B.  perennis,  Linn.  English  daisy.  European  garden  daisy.  Fig.  200. 
Flower-head  on  a  scape  3-4  inches  high,  from  radical  leaves,  %-l  in.  in 
diameter,  with  numerous  linear  rays,  white,  pink,  bluish.  Europe.  Perennial. 
Cultivated  in  gardens  or  on  lawns.  April  to  November. 

IS.  HELIANTHUS.    Sunflower.    Figs.  3,  4. 

Stout,  often  coarse  perennials  or  annuals,  with  simple  alternate  or 
opposite  leaves  and  large  yellow-rayed  heads:  ray  florets  neutral;  scales  of 
involucre  overlapping,  more  or  less  leafy ;  torus  flat  or  convex,  with  a  bract 
embracing  each  floret:  achene  4-angled:  pappus  of  2  scales  (sometimes  2 
other  smaller  ones),  which  fall  as  soon  as  the  fruit  is  ripe. 

a.  Disk  brown. 

H.  annuus,  Linn.  Common  sunflower.  Tall,  rough,  stout  annual,  with 
mostly  alternate  stalked  ovate-toothed  large  leaves:  scales  of  involucre  ovate- 
acuminate,  ciliate.   Minnesota  to  Texas  and  West,  but  everywhere  in  gardens. 

H.  scaberrimus,  Ell.  Prairie  sunflower.  Stout  perennial  (2-6  ft.),  rough: 
leaves  oblong-lanceolate,  entire  or  serrate,  rough  and  grayish,  thick  and 
rigid:  heads  nearly  solitary,  with  20-25  rays.    Prairies,  Michigan,  west. 

aa.   Disk  yellow  (anthers  sometimes  dark). 

H.  giganteus,  Linn.  Tall,  to  10  ft.,  rough  or  hairy:  leaves  mostly 
alternate,  lanceolate-pointed,  finely  serrate  or  quite  entire,  nearly  sessile: 
scales  linear-lanceolate,  hairy;  rays  pale  yellow,  15-20.    Low  grounds. 

H.  divaricatus,  Linn.  Figs.  3.  4,  23,  28.  Small  for  the  genus,  1-4  ft.: 
leaves  opposite,  ovate-lanceolate,  3-nerved,  sessile,  serrate,  rough  and 
thicVish:  rays  8-12,  1  in.  long.    Common  in  dry  thickets. 

H.  tuberosus,  Linn.  Jerusalem  artichoke.  Bearing  edible  stem-tubers 
below  ground:  5-10  ft.:  leaves  ovate  to  oblong-ovate,  toothed,  long-petioled: 
scales  not  exceeding  the  disk:  rays  12-20,  large.  Pennsylvania  west,  and 
cultivated. 

19.  TANACETUM.    Tansy. 

Tufted  perennials,  with  finely  divided  leaves  and  strong  odor:  involucre 
of  overlapping  dry  scales;  torus  convex;  heads  small,  nearly  or  quite  rayless, 
the  flowers  all  seed-bearing:  achenes  angled  or  ribbed,  bearing  a  short 
crown-like  pappus. 

T.  vulgare,  Linn.  Common  tansy  from  Europe,  but  run  wild  about  old 
houses:  2-4  ft.:  leaves  1-3-pinnately  cut:  heads  yellow,  pappus-crown 
5-lobed. 


440 


THE    KINDS    OF    PLANTS 


V 


20.  BIDENS.   Bur-marigold.   Beggar's  Ticks.   Pitchforks. 

Annual  or  perennial,  similar  to  Coreopsis,  including  weeds  known  as 
Spanish-needles  or  stick-tights:  leaves  opposite:  flowers  mostly  yellow; 
involucre  double,  outer  scales  large  and  leaf-like;  heads  many -flowered ; 
ray  flowers  4-8,  neutral,  or  none;  disk  flowers  perfect,  tubular:  achenes 
flattened  or  slender  and  4-angled,  crowned  with  2  or  more  rigid  downwardly 
barbed  awns. 

B.  frondosa,  Linn.  Figs.  418,  558. 

Smooth  or  sparsely  hairy,  2-6  ft.  tall, 

branching:     leaves     3-5-divided,     or 

upper  simple;  leaflets  stalked,  lanceo- 

'■    '  ,'r">         late,    serrate:  outer   involucre   longer 

^  '^O      than  head;  bracts  foliaceous:  achenes 

\t   wedge-ovate,  flat,  2-awned.    In  moist 

places.    Annual. 

B.  lsevis,  BSP.  Smooth  branching 
annual,  6  in.  to  2  ft.,  usually  abundant  along 
ditches:  leaves  sessile,  simple,  lanceolate,  acumi- 
nate, serrate,  the  bases  sometimes  united:  outer 
involucral  bracts  exceeding  the  inner,  but  shorter 
than  the  yellow,  oval  or  oblong  rays:  rays  about  1 
in.  long,  8  or  10  in  number:  achenes  small,  wedge- 
shaped,  truncate,  prickly  on  margins,  with  2  rigid 
downwardly  barbed  awns. 

B.  bipinnata,  Linn.  Spanish  needles.  Annual: 
stem  quadrangular,  erect,  branching  freely:  leaves 
1-3  times  pinnate,  leaflets  lanceolate,  pinnatifid: 
heads  small  on  slender  peduncles;  rays  short,  pale 
yellow,  3,  4  or  more:  achenes  smooth,  3-4-grooved, 
2-  or  6-awned  (awns  barbed). 

21.  COREOPSIS.    Tickseed. 

Low  herbs  with  opposite,  sometimes  alternate  leaves: 
heads  of  tubular  and  ray  flowers  solitary,  or  corymbed  on 
long  peduncles;  involucre  double,  bracts  all  united  at 
base,  the  8  outer  ones  usually  leafy;  the  inner  erect;  re- 
ceptacle chaffy;  ray  flowers  neutral,  usually  yellow;  disk 
flowers  tubular,  perfect,  yellow  or  purple;  pappus  of  2  short  teeth  or  a 
crown-like  border,  or  none:  achenes  flat,  often  winged,  2-toothed  or  2- 
armed.    A  number  of  rather  showy  but  somewhat  weedy  plants. 

C.  tinctoria,  Nutt.  Calliopsis.  Annual  or  biennial,  glabrous,  erect,  1-3 
ft. :  disk  flowers  dark  purple ;  ray  flowers  about  8,  yellow  with  purple  bases, 
the  edges  coarsely  3-toothed:  leaves  alternate,  2  or  3  times  pinnately- 
divided;  the  lower  petioled,  the  upper  sessile  and  often  entire:  heads  1-1 J^ 
in.  wide,  on  slender  peduncles.  A  favorite  in  gardens.  Ray  flowers  variable 
in  shape  and  coloring. 

C.  tripteris,  Linn.    Tall  coreopsis.   Tall  and  leafy  stems,  4-9  ft. :  disk  and 


COMPOSITES 


441 


ray  flowers  all  yellow;  heads  small,  numerous,  1-1^  in.  broad,  eorymhed,. 
giving  a  spicy  odor  when  bruised.    Perennial.    Weed,  common. 

C.  lanceolata,  Linn.  Perennial,  native  and  cultivated:  nearly  or  quite 
glabrous:  leaves  oblong  or  linear,  mostly  entire,  obtuse:  heads  large,  yellow- 
rayed,  on  very  long  stems. 

22.  CiRSIUM.    Thistle. 

Perennial  or  biennial  herbs,  with  pinnatifid,  very  prickly  leaves:  florets 
all  tubular  and  usually  all  perfect;  scales  of  the  involucre  prickly;  torus 
bristly;  pappus  of  soft  bristles,  by  means  of  which  the  fruit  is  carried  in  the 
wind.    Several  species  in  our  territory. 

C.  lanceolatum,  Hill.  Common  thistle.  Figs.  253-255.  Strong,  branching 
biennial:  leaves  pinnatifid,  decurrent,  woolly  beneath:  heads  large,  purple, 
with  all  the  involucre-scales  prickly.    Europe. 

C.  arvense,  Scop.  Canada  thistle.  Fig.  409.  Lower,  perennial  and  a  pes- 
tiferous weed:  leaves  smooth  or  nearly  so  beneath:  flowers  rose-purple,  in 
small,  imperfectly  dioecious  heads,  only  the  outer  scales  prickly.    Europe. 

23.  ARCTIUM.    Burdock. 

Coarse  biennials  or  perennials,  strong-scented,  with  large  dock-like 
simple  leaves:  head  becoming  a  bur  with  hooked  bristles,  the  florets  all 
tubular  and  perfect;  torus  bristly;  pappus  of  short,  rough,  deciduous  bristles. 

A.  Lappa,  Linn.    Burdock.    Common  weed  from  Europe,  with  a  deep, 
hard  root,  and  bushy  top  2-3  ft.  high:   leaves  broad-ovate, 
somewhat  woolly  beneath,  entire  or  angled. 

24.  CENTAUREA.    Star-thistle.    Centaurea. 
Alternate-leaved  herbs,  the  following  annuals,  with  single 

heads  terminating  the  long  branches:  heads  many-flowered, 
the  florets  all  tubular  but  the  outer  ones  usually  much  larger 


$59.   Centaurea  Cyanus.    At  the  left  is  an  outer  or  ray  floret;  then  follow  three 
details  of  a  disk  floret;  then  follows  the  fruit. 


442  THE    KINDS    OF    PLANTS 

and  sterile;  scales  of  involucre  overlapping;  torus  bristly:  achenes  oblong, 
with  bristly  or  chaffy  pappus.    Cultivated. 

C.  Cyanus,  Linn.  Corn-flower.  Bachelor's  button.  Figs.  256,  559.  Gray 
herb:  leaves  linear  and  mostly  entire:  heads  blue,  rose  or  white.    Europe. 

C.  moschata,  Linn.  Sweet  sultan.  One  to  2  ft.,  smooth:  leaves  pinnatifid: 
pappus  sometimes  wanting;  heads  fragrant,  white,  rose  or  yellow;  large.  Asia. 

25.  TUSSILAGO.    Coltsfoot. 

Low  stemless  hairy  perennials  from  rootstocks:  scapes  simple  in  early 
spring,  scaly-bracted,  each  bearing  a  single  dandelion-like  head:  leaves 
radical,  appearing  later,  orbicular-angled  or  toothed,  white- woolly  at  first: 
ray  flowers  in  several  rows,  pistillate,  fertile;  disk  flowers  tubular,  stam- 
inate,  sterile;  involucre  nearly  simple,  or  1-rowed  achenes  of  ray  flowers, 
cylindrical,  5-10-ribbed;  pappus  abundant,  soft,  hair-like,  white. 

T.  Farfara,  Linn.  Yellow  heads  in  very  early  spring  before  the  leaves.  A 
common  weed  East,  found  in  low,  damp  places  and  along  cool  banks.  Europe. 

26.  SOLIDAGO.    Goldenrod. 

Perennial  herbs,  with  narrow,  sessile  leaves:  heads  yellow,  rarely  whitish, 
few-flowered,  usually  numerous  in  the  cluster,  the  ray-florets  1-16  and 
pistillate;  scales  of  involucre  close,  usually  not  green  and  leaf -like;  torus 
not  chaffy:  achene  nearly  cylindrical,  ribbed,  with  pappus  of  many  soft 
bristles.  Of  goldenrods  there  are  many  species.  They  are  characteristic 
plants  of  the  American  autumn.    They  are  too  critical  for  the  beginner. 

27.  INULA.    Elecampane. 

Large  and  tall  coarse  perennial  herbs,  with  large,  showy  yellow  flower- 
heads  2-4  in.  diameter,  sunflower-like:  leaves  large,  simple,  alternate, 
and  also  radical  in  clumps:  heads  contain  both  perfect  tubular,  and  pistil- 
late ray  florets,  in  one  row;  receptacle  not  chaffy:  achenes  4— 5-ribbed: 
pappus  in  one  row,  bristles  hair-like. 

I.  Helenium,  Linn.  Four  to  6  ft.,  rising  from  a  clump  of  large,  ovate, 
dock-like  leaves  on  heavy  petioles;  stem-leaves  sessile  or  clasping:  heads 
solitary,  terminal;  involucre  bracts  ovate,  leaf-like,  woolly.  Weed  in  damp 
pasture  and  along  roadside.    Summer. 

28.  ASTER.    Aster.    Fig.  252. 

Perennial  herbs,  with  narrow  or  broad  leaves:  heads  with  several  to 
many  white,  blue  or  purple  rays  in  a  single  series,  the  ray  florets  fertile; 
scales  of  involucre  overlapping,  usually  more  or  less  green  and  leafy;  torus 
flat:  achene  flattened,  bearing  soft,  bristly  pappus.  Asters  are  conspicuous 
plants  in  the  autumn  flora  of  the  country.  The  kinds  are  numerous,  and  it 
is  difficult  to  draw  specific  lines.    The  beginner  will  find  them  too  critical. 

29.  ERIGERON.    Fleabane. 

Annual,  biennial  or  perennial  erect  herbs,  with  simple,  sessile  leaves: 
heads  few-  to  many-flowered;  rays  numerous  in  several  rows  and  pistillate; 


COMPOSITES 


443 


scales  of  involucre  narrow  and  equal,  scarcely  overlapping,  not  green-tipped; 
torus  flat  or  convex,  naked;  pappus  of  soft  bristles. 

a.  Rays  very  inconspicuous. 
E.  canadensis,  Linn.     Horse-weed.    Mare's-tail.     Fig.  560.    Tall,  erect, 
weedy,  hairy  annual,  with  strong  scent:  leaves  linear  and  mostly  entire  or 
the  root-leaves  lobed:  heads  small  and  very  numerous  in  a  long  panicle, 
the  rays  very  short. 

aa.  Rays  prominent:  common  fleabanes. 

E.  annuus,  Pers.  Usually  annual,  3-5  ft.,  with  spreading 
hairs:  leaves  coarsely  and  sharply  toothed,  the  lowest  ovate 
and  tapering  into  a  margined  petiole:  rays  numerous,  white 
or  tinged  with  purple,  not  twice  the  length  of  the  involucre. 

E.  ramosus,  BSP.  Daisy  Jtcabane.  Usually  annual,  with 
appressed  hairs  or  none:  leaves  usually  entire  and  narrower: 
rays  white  and  numerous,  twice  the  length  of  the  involucre. 

E.  pulchellus,  Michx.  Robin's  plantain.  Perennial  leafy- 
stemmed  herb,  softly  hairy,  producing  stolons  or  rooting 
branches  from  the  base,  the  simple  stems,  from  a  cluster  of 
rather  large,  roundish,  short-petioled,  serrate,  root-leaves; 
stem-leaves  few,  entire,  sessile  and  partially  clasping:  heads 
1-7,  on  long  peduncles;  rays  numerous,  linear  or  spatulate, 
purplish  or  pinkish.     April  to  June. 

30.  CALLISTEPHUS.    China  Aster. 


50!  >.  Erigeron 
canadensis. 


Erect,  leafy  annuals,  with  large  solitary  heads  bearing 
numerous  white,  rose  or  purple  rays:  scales  in  several  rows  or  series, 
usually  leafy;  torus  flat  or  nearly  so,  naked;  pappus  of  long  and  very  short 
bristles. 

C.  hortensis,  Cass.  Common  China  aster,  now  one  of  the  commonest  of 
garden  annuals,  in  many  forms:  leaves  sessile  and  coarsely  toothed.    China. 

31.  ANTENNARIA.   Everlasting. 

Perennial  little  herbs  with  cottony  leaves  and  stems:  flowers  dioecious, 
in  many-flowered  small  heads,  solitary  or  racemose  or  clustered  (much 
resembling  Gnaphalium,  but  distinguished  by  the  dioecious  heads);  invo- 
lucre with  dry  imbricated  bracts  in  several  rows,  usually  woolly-white  or 
colored;  pappus  in  a  single  row,  that  of  the  sterile  flowers  thickened  and 
plumed  at  summit.  Several  confused  species,  or  forms  of  one  species,  mostly 
in  open,  dry  places. 

A.  plantaginifolia,  Rich.  Mouse-ear  everlasting.  Noticeable  on  dry 
soil  and  in  open  places,  as  white  cottony  patches:  stoloniferous  root-leavea 
soft  white  when  yountr,  later  green  above  but  hoary  beneath,  oval  tn  spatu- 
late, petioled,  3-veined:  flowering  stem  simple  scape-like,  4—8  in.  high, 
bears  small,  bract-like,  appressed  leaves,  and  heads  in  a  small,  crowded, 
terminal  corymb;  scales  of  involucre  whitish. 


444  THE    KINDS    OF    PLANTS 

32.  ANAPHALIS.   Everlasting. 

Cottony-white  herbs,  very  similar  to  the  preceding,  but  pappus  not 
thickened  at  summit,  and  usually  a  few  perfect  but  sterile  flowers  in  center 
of  the  head:  stem  leafy.    Perennial. 

A.  margaritacea,  Benth.  &  Hook.  Pearly  everlasting.  One  to  2  ft.: 
heads  in  corymbs  at  summit,  dioecious,  but  a  few  imperfect  staminate 
flowers  in  the  center  of  the  fertile  heads:  leaves  sessile,  taper-pointed, 
broad-ovate  to  linear-lanceolate:  involucre  scale  pearly  white,  rounded. 
Common  in  dry  soil. 

33.  GNAPHALIUM.    Everlasting.    Cudweed. 

Cottony-white  herbs,  with  small  head  of  many  whitish  flowers,  sur- 
rounded by  involucre  of  white  or  colored  scales,  in  many  series:  flowers  all 
fertile,  outer  pistillate,  central  perfect:  no  chaff  on  receptacle;  pappus  a 
row  of  slender  bristles.    Common  in  dry  fields. 

G.  polycephalum,  Michx.  Common  everlasting.  Annual,  with  leaves 
lanceolate,  margins  wavy,  upper  surface  not  very  cottony:  scales  of  invo- 
lucre white  or  yellowish  white,  a  few  perfect  flowers  in  the  center  of  each 
head. 

G.  decurrens,  Ives.  Biennial  or  annual,  with  many  perfect  flowers  in 
center  of  each  head:  stem  erect,  1-2  ft.:  leaves  lance-linear,  both  sides 
cottony,  bases  partially  clasping  and  running  down  the  stem. 

34.  LlATRIS.    Blazing  Star.    Button  Snakeroot. 

Perennial  herbs,  with  simple  erect  stems  from  tuberous  or  corm-like 
roots:  leaves  entire,  alternate,  rather  rigid,  sometimes  vertical  on  the  stem, 
and  resinous-dotted:  flowers  few  to  many,  in  racemed  or  spicate  heads; 
flowers  all  alike,  rose-purple,  tubular;  corolla  5-lobed,  lobes  long  and 
slender;  pappus  of  many  hair-like  bristles,  plumose  or  barbed:  achene 
slender,  tapering  to  base:  involucral  bracts  in  several  rows,  unequal. 

L.  scariosa,  Willd.  Stem  stout,  2-5  ft.  tall:  leaves  lanceolate,  the  lower 
long-petioled,  the  upper  more  linear  and  rigid :  heads  few  to  many,  30-40- 
flowered,  about  1  in  broad:  scales  of  involucre  numerous,  with  rounded 
tips;  often  colored  and  rather  rough  on  the  margins;  flowers  bright  purple. 
Dry  soil. 

L.  pycnostachya,  Michx.  Heads  3-15-flowered:  flowers  rosy-purple  on  a 
spike  3-4  ft.  high:  flowers  begin  to  open  at  top  of  the  spike  and  continue 
opening  downward:  scales  with  purplish  tips.  A  western  species,  cultivated; 
very  showy. 

35.  EUPATORIUM.   Thoroughwort. 

Erect  perennials,  with  simple  leaves:  heads  small  and  rayless,  clustered, 
all  the  florets  perfect;  scales  not  leafy;  torus  flat  or  low-conical,  naked: 
achene  5-angled:  pappus  a  single  row  of  soft  bristles.    Low  grounds. 

E.  purpureum,  Linn.  Joe  Pye  weed.  Tall,  with  purplish  stem  and  lan- 
ceolate-toothed leaves  in  whorls  of  3-6:  heads  flesh-colored,  in  dense 
corymbs.    Swamps,  growing  3-10  ft. 


I 


COMPOSITES  445 

E.  perfoliatum,  Linn.  Boneset.  Thoroughwort.  Fig.  171.  Two  to  4  ft., 
hairy:  leaves  opposite  and  sessile,  lanceolate:  flowers  white,  in  clusters. 

36.  VERNONIA.    Ironweed. 

Coarse  perennial  herbs,  with  tall  strong  leafy  stems:  leaves  alternate 
(seldom  opposite),  sessile:  flowers  15  to  many  in  a  head,  heads  corymbed, 
all  tubular,  perfect,  purple  (rarely  white  or  pink);  involucre  shorter  than 
flowers,  with  several  series  of  scales;  receptacle  not  chaffy;  pappus  double, 
the  inner  scries  bristle-like,  the  outer  of  short,  small,  scale-like  bristles: 
achenes  cylindrical,  several-ribbed. 

V.  novaboracensis,  Willd.  A  coarse  weed,  3-6  ft.:  heads  about  Yi  in- 
long:  bracts  of  involucre,  some  or  all,  with  slender  long  or  awned  flexxious 
points,  brownish  purple:  leaves  many,  rough,  lanceolate  or  lance-oblong, 
2-9  in.  long,  serrulate,  sessile,  all  along  stem:  flowers  deep  purple  in 
spreading,  flat-topped  cymes:  achenes  somewhat  hairy.    Late  summer. 

V.  fasciculata,  Michx.  Tall,  coarse  weed,  3-10  feet,  with  deep  purple 
flowers  in  heads  (20-30-flowered),  corymbed;  involucre  campanulate, 
scales  usually  obtuse,  not  awn-like.    Summer  and  autumn. 


INDEX  AND   GLOSSARY 

Numbers  in  parenthesis  refer  to  paragraphs 


Aborted:  crowded  out,  (316). 

Abronia,  Fig.  18. 

Abutilon,  372,  Figs.  182,  520. 

Acacia,  leaf,  108,  Fig.  103. 

Accessory  buds:  more  than  one  in  an  axil, 

(88). 
Accessory  fruit:  other  parts  grown  to  the 

pericarp,  (311),  161. 
Acclimatization:  adaptation  to  a  climate 

at  first  injurious,  (367). 
Acer,  376,  Figs.  523-526. 
Acetic  acid,  271. 
Achene:     dry,     indehiscent,     one-seeded 

pericarp,  (313). 
Achillea,  437. 
Acorn,  155,  178. 
Acorus,  328. 
Actsea,  359. 

Acuminate:  taper-pointed,  (211). 
Acute:  sharp-pointed,   (211). 
Adder's-tongue,  331;  fern,  198,  Fig.  36S. 
Adiantum,  323. 
Adventitious   buds:   those   appearing   on 

occasion,  (54,  124). 
.Ecidia,  191.    /Ecidiospore,  191. 
Aerial  roots,  10,  Figs.  12-14. 
-Esculus,  377. 
Ageratum,  437. 

Aggregate  fruit:  one  formed  by  the  co- 
herence of    pistils    that    were    distinct 

in  the  flower,  (321). 
Agrimonia,  387. 
Agrimony,  169,  387. 
Ailanthus,  leaf-scars,  37,  Figs.  57;  seeds, 

168. 
Air-plants,  11. 
Alcanin,  273. 
Alder.  345. 

Aleurone  grains,  275,  Fig.  445. 
Alfalfa,  3,  7,   .9,  94,  137,   172,  251,  383, 

Figs.  21,  246,  529;  nodules  on  root,  7S. 
Alga;,  181,  183,  185,  201,  207,  263,  266. 
Alkaloids,  271. 

Almond,  61,  251,  271;  bud,  39,  Fig.  68. 
Alnus,  345. 
Alpine  plants,  229. 
Alsike  clover,  382. 
Alternate  leaves,  47. 
Alternation  of  generations,  182,  201. 
Althea,  148,  372,  373. 
Alyssum,  160,  367,  368,  Fig.  519. 


Amaranth,  170,  Fig.  411. 

AmaryllidaceK,  335. 

Ambrosia,  436,  Figs.  416,  556. 

Amelanchier,  391. 

Amoeba,  206.   Amoeboid,  266. 

Ampelopsis,  leaves  of,  100,  Fig.  155. 

Amphibious,  208. 

Aniylo-dextrine,  275.    Amylose,  271. 

Anacharis,  85,  Fig.  439. 

Analogy:  related  in  function  or  use,  (223). 

Anaphalis,  444. 

Anemone,  356;  fruit,  156. 

Anemonella,  357. 

Angelica,  398. 

Angiosperms,  327. 

Aniline  for  staining,  73. 

Annual:  of  one  season's  duration,  (10). 

Annular,  267. 

Antennaria,  443. 

Anthemis,  437,  Fig.  417. 

Anther:  pollen-bearing  part  of  the  sta- 
men,  (270). 

Antheridia,  181,  187.  Antheridiophore, 
194. 

Anthodium:  flower-head  of  the  Com- 
positse,  (251). 

Antirrhinum,  406. 

Antitropic:  against  the  sun,  (243). 

Apetalous:  petals  missing,    (273,  290). 

Aphyllon,  90,  Fig.  131. 

Apical;  at  the  apex  or  top,  (317). 

Apios,  385. 

Apium,  399. 

Apocynacea;,  418. 

Apparatus,  301. 

Apple,  20,  32,  68,  251,  254,  391 ;  acid,  271; 
bud,  36,  39,  40,  Fig.  71;  bud-variation, 
23N;  cells,  2iV.l,  265;  foliage,  65;  fruit, 
162,  Fig.  295;  inflorescence,  123,  Fig. 
294;  leaf,  83;  leaf-scar,  37;  pear-graft, 
28;  phyllotazy,  48,  Fig.  84;  pruning, 
Pigs.  102,  104;  thorns,  IDS;  tree,  14, 
64,  93,  220,  Fig.  17. 

Apricot,  251,  366;  bud,  37,  39,  41,  Figs. 
55,  6S;  fruit,   161. 

Aquatic,  207;  society,  Fig.  401. 

Aquilegia,  35S,  Fig.  517. 

Arabia,  388,  Fig.  536. 

\i aces,  .!27. 

Arboriculture,  257. 

Arborvitse,  326,  Figs.  404,  405,  486. 


(447) 


448 


INDEX    AND     GLOSSARY 


Arbutus,  trailing,  425. 
Archegoniophore,    194.   Archegonium, 

181. 
Arctium,  441. 
Arisaema,  327. 
Aristolochiaceffi,  348. 
Arrow-root,  starch,  274,  275. 
Arrowwood,  429. 
Artichoke,  Jerusalem,  439. 
Arum,  family,  149,  327;  water,  328. 
Asarum,  349. 
Ascending  stems,  14. 

Asclepiadacese,  417.    Asclepias,  283,  418. 
Ascus,  190. 
Ash,  421;  branching,  56,  Fig.   92;  fruit, 

156;    leaf,    Fig.    141;    mountain,    391; 

phyllotaxy,  4S;  seeds,  108. 
Ash  in  plants,  77. 
Asparagus,   3,   285,   289,   333,   Figs.  457, 

458;  leaves,  107,  Figs.  159-162. 
Aspen  (poplarl,  expression  in,  66. 
Aspidium,  289,  323,  324,  Figs.  331,  332, 

480. 
Asplenium,  323. 
Assimilation:     making     of     protoplasm, 

(185,  186). 
Aster,  233,  442;  China,  443;  inflorescence, 

120,  150,  151;  wild,  252,  Fig.  146. 
Atropin,  271. 
Auricula,  422. 
Autumn  leaves,  233. 
Avens,  386. 
Axil:    upper    angle    which    a    petiole    or 

peduncle  makes  with  the  stem  which 

bears  it,  (87). 
Axillary,  119,  Fig.  201. 
Azalea,  425;  anther,  135,  Fig.  220. 

Bachelor's  button,    151,   442,   Figs.   256, 
'      559. 
Bacterium    (pi.    bacteria),    91,   263,   278, 

Fig.  136. 
Ballast  plants,  170. 
Balloon-vine,  376. 
Balsam,   33,    166,   286;  garden,   375;   for 

mounting  sections,  303. 
Bamboo,  forest,  Fig.  437. 
Baneberry,  359. 
Banyan,  11,  20,  Fig.  15. 
Baptisia,  383. 
Barberry,    360;    anther,    135,    Fig.    221; 

family,  360;  rust,   191,   192,  Figs.  355, 

356;  spines,  109,  Fig.  168. 
Bark,  293;  forms  of,  65. 
Barley,  152,  250,  Fig.  261;  germination, 

173. 
Basal:  at  the  base  or  bottom,  (317). 
Basidium,  191. 
Basswood,  37,  292;  phyllotaxy,  48,  Fig. 

464. 
Bast,  280,  281,  Fig.  450. 


Bean,  castor,  4, 171, 175, 178,271,273,352, 
Figs.  313-316;  common,  3,  7,  166.  250, 
384,  Figs.  2,  530;  germination,  171, 
173,  174,  178,  Figs.  308-312,  322; 
legume,  157;  Lima.  175,  384,  Fig.  531; 
scarlet  runner,  174,  178,  384;  sleep  of, 
49;  twiner,  115,  116. 

Beard-tongue,  406. 

Bedstraw,  112,  426. 

Bee  balm,  400. 

Beech,  64,  67,  343;  drop,  90;  European, 
98;  fruit,  155;  leaf,  Fig.  151;  monoe- 
cious,  138. 

Beefsteak  geranium,  Fig.  41. 

Beet,  7,  33,  250,  251;  cells,  265;  starch  in, 
31;  sugar-,  251,  273. 

Beggar's  ticks,  440,  Fig.  558. 

Begonia,  cells,  265;  cuttings,  21,  27,  Fig. 
41;  leaf,  298,  Fig.  144;  stomates,  301, 
Fig.  473. 

Belladonna,  271. 

Bell-flower,  430;  family,  430. 

Bellis,  439. 

Bellwort,  332. 

Berberidacere,  360. 

Berry:  pulpy,  indehiscent,  few-  or  many- 
seeded  fruit,   (319). 

Betula,  344. 

Bi-collateral,  288. 

Bi-compound,  96. 

Bidens,  440,  Figs.  418,  558. 

Biennial:  of  two  seasons'  duration,  (10). 

Bilberry,  424. 

Bindweed,  244,  412. 

Birch,  231,  344. 

Birthroot,  333. 
[    Birthwort,  family,  348. 
I    Bishop's  cap,  394. 

Bitter-cress,  307. 

Bittersweet,  248,  409,  Fig.  424;  climbing, 
112;  false,  twiner,  115,  Fig.  179. 

Blackberry,  20,  251,  390;  cutting.  ,  23; 
fruit,  160,  161;  pruning,  61;  and  Lirds, 
168. 

Black-eyed  Susan,  438,  Fig.  557. 

Black  haw,  Fig.  305. 

Bladder-nut,  378. 

Bladder-wort,  71,  207. 

Blade:  expanded  part  of  leaf  or  petal, 
(206). 

Blazing  star,  444. 

Bleeding  of  plants,  73. 

Bleeding-heart,  3,  364. 

Blight,  92.    Blight-canker,  92. 

Bloodroot,  363. 

Blueberry,  424. 

Blue-eyed  grass,  338. 

Blue-eyed  Mary,  406. 

Blue-grass,  246. 

Bluets,  427. 
|    Bole:   trunk,  (140). 


INDEX    AND     GLOSSARY 


449 


Boneset.  445,  Fig.  138;  bracts,  171. 

Borage  family,  412. 

Boreal  plants,  229. 

Borraginacea:,  412. 

Boston  ivy,  leaves,  100,  Fig.  155;  tendril, 

113. 
Bougainvillea,  110. 
Bouncing  Bet,  354;  fruit.  Fig.  282. 
Box,  leaf,  Fig.  149. 
Box-elder,  370;  phyllotaxy,  47,  48,  Fig. 

84. 
Bracts:  much  reduced  leaves,  (231). 
Brake,  180,  207,  323,  Figs.  139,  335,  456 
Bramble,  3S9. 

Branched  stem,   15,  Fig.  21. 
Brassica,  365,  Fig.  518. 
Briars,  climbing,   112;  prickles,  109. 
Bridal  wreath,  121,  392,  Fig.  193. 
Bristles,  109. 

Bryophyllum,  leaf  cuttings,  21. 
Bryophyte,  183. 
Buckeye,  377. 
Buckwheat,  76,  251,  350,  Fig.  513;  family, 

349;  flower,  130;  fruit,  156;  pollination, 

139. 
Bud,  Fig.  165;  dormant,  54;  propagation 

by,  21;  resting,  36;  -scales,  111;  -scars, 

old,  54,  Fig.  91;  struggle  for  existence, 

52;  winter,  21,  36,  61;  and  light,  50; 

-variations,  237. 
Bulb:  thickened  part,  made  up  of  scales 

or  plates,   (80);  phyllotaxy,  48;  scales, 

111. 
Bulbel:  bulb  arising  from  a  mother  bulb, 

(81). 
Bulblet:  aerial  bulb,  21,  (81). 
Burdock,  7,  67,   169,  242,  243,  441,  Fig. 

306. 
Burning  bush,  294. 
Bur-marigold,  440,  Fig.  558. 
Burs,  169. 
Bur-seed,  413. 

Burst  of  spring,  40,  Fig.  72. 
Bushes:  low  and  thick  shrubs,  (15). 
Butter-and-eggs,  137,  145,  405,  Figs.  227, 

544. 
Buttercup,  3,  208,  233,  357;  achene,  156, 

Fig.    268;    family,    355;    flower,    Figs. 

202,  203;  pistil,  130,  Fig.  207 
Butterfly  weed,  418. 
Butternut  buds,  37. 
Button-bush,  427. 
Button  snakeroot,  444. 
Buttonwood,  294. 
Buttresses,  bracing,  9,  Fig.  10. 

Cabbage,   12,   16,   251;   fruit,    160;  head, 

37,  38,  Fig.  59;  water  pores,  299. 
Cacti,  Fig.  371. 
Caffein,  271. 
Calamus,  328. 

cc 


Calcium,  70;  oxalate,  271,  275. 

Calendula,  438. 

Calla,  328,  Figs.  486,  487;  inflorescence, 
150;  lily,  328,  Fig.  486. 

Calliopsis,  440. 

Callistephus,  443. 

Callus,  62. 

Caltha,  358. 

Calypogon,  342. 

Calyptra,  197. 

Calyx:  outer  circle  of  floral  envelopes, 
(265);  lobes,  (266). 

Cambium:  the  growing  or  nascent  tissue 
lying  between  the  xylem  and  phloem 
of  the  fibro-vascular  bundle  (481),  and 
therefore  on  the  outside  of  the  woody 
trunk,  since  the  active  fibro-vascular 
bundles  are  in  the  young  outer  tissues 
(72),  62. 

Campanula,  430;  capsule,  Fig.  283. 

Campanulacea,  430. 

Campion,  354. 

Canada  thistle,  19,  22,  242,  244,  Fig. 
409. 

Candytuft,  368,  Fig.  192. 

Canker,  92. 

Canna,  18,  Fig.  29. 

Cannabis,  348. 

Canterbury  bell,  430. 

Caoutchouc,  271. 

Caprifoliacea,  427. 

Capsella,  368. 

Capsicum,  410,  Fig.  547. 

Capsule:  compound  pod,  (316). 

Caraway,  399. 

Carbohydrate,  85. 

Carbon,  76,  82;  dioxid,  77,  82. 

Cardamine,  367. 

Cardinal-flower,  431. 

Cardiospermum,  376. 

Carnation,  254,  255,  353;  cutting,  25, 
Figs.  34,  36. 

Carpel:  a  simple  pistil;  one  of  the  units 
of  a  compound  pistil,  (271). 

Carrot,  3,  33,  242,  243,  398,  Fig.  410; 
umbel,  121,  122,  Fig.   194. 

Carum,  399. 

Caryophyllaceffi,  353. 

Cassia,  385;  flower,  146,  Fig.  247. 

Castalia,  361. 

Castanea,  343. 

Castilleja,  407. 

Castor  bean,  4,  271,  273,  352;  germina- 
tion, 171,  175,  178,  Figs.  313-31ti. 

Castor-oil,  273;  inclusions,  275,  276; 
plant,  352. 

Catalpa,  pods,  160,  Fig.  284;  seeds,  168, 
Fig.  301. 

Catchfly,  354. 

Catkin:  scaly-bracted  deciduous  spike 
with  declinous  flowers,  (252). 


450 


INDEX    AND     GLOSSARY 


Catmint,  403. 

Catnip,  131,  243,  403,  Figs.  213,  414. 

Cat-tail,  3;  seeds,  168,  Fig.  304;  stems, 
285;  swamp,  232. 

Caulicle:   stemlet  of  the  embryo,    (332). 

Cedar,  326,  327,  Fig.  485;  and  light,  Fig. 
76;  fruit,  164;  and  birds,  168;  apple, 
192. 

Celandine,  265,  363. 

Celastrus,  twiner,  115. 

Celery,  249,  399;  cell,  265. 

Cell,  263;  multiplication,  268,  Figs.  442, 
443;  -sap,  72,  76,  265;  -wall,  88,  264, 
266,  Fig.  267. 

Cellulose,  266,  271. 

Celtis,  347. 

Centaurea,  441,  Fig.  559. 

Centrifugal:  away  from  the  center,  (258), 
Fig.  199. 

Centripetal:  toward  the  center,  (258), 
Figs.  197,  198. 

Cephalanthus,  427. 

Cerastium,  355. 

Cercis,  351. 

Chamberlain,  quoted,  303. 

Chamomile,  437. 

Chara,  266. 

Charcoal,  82. 

Charlock,  243,  366,  368,  Fig.  413. 

Cheat,  Fig.  412. 

Checkerberry,  424. 

Cheeses,  147,  148,  244,  372,  Fig.  248. 

Chelone,  406. 

Chenopodium,  Fig.  408. 

Cherry,  20,  251,  387,  388,  Fig.  539;  fruit, 
161;  inflorescence,  123;  phyllotaxy,  48; 
and  birds,  168. 

Chess,  242,  Fig.  412. 

Chestnut,  343;  fruit,  155,  Fig.  267;  monoe- 
cious, 138;  -oak  graft,  28. 

Chickweed,  242,  355,  Fig.  516;  mouse- 
ear,   355. 

Chicory,  435. 

Chinese  sacred  lily,  336,  Fig.  494. 

Chionanthus,  421. 

Chlorin,  76,  82. 

Chlorophyll,  83,  270. 

Chloroplast,  264. 

Choke  cherry,  389. 

Choripetalae,  3<-2. 

Chromosome,  268. 

Chrysanthemum,  150,  151,  153,  438. 

Cichorium,  435. 

Cider,  acid,  271. 

Cilia,  186,  266. 

Cinchona,  271. 

Cinquefoil,  386. 

Cion :  the  bud  or  branch  used  in  grafting, 
(70). 

Circa;a,  397. 

Cirsium,  441. 


Citric  acid,  271. 

Cladophyllum:  leaf-like  branch,   (225). 

Clasping:  leaf  partly  or  wholly  surround- 
ing stem,   (207). 

Claytonia,  371. 

Cleavers,  426. 

Cleft,  96.   Cleft-graft,  29. 

Cleistogamous  flowers:  small  closed  self- 
fertilized  flowers,  (286). 

Clematis,  155,  287,  359;  and  light,  Fig. 
77;  tendril,  115,  Fig.  178. 

Climate,  and  plants,  212;  and  variation, 
238. 

Climbing,  plants,  112;  plants  and  light, 
43;  stems,  14. 

Close  fertilization:  secured  by  pollen 
from  same  flower;  self-fertilization, 
(278). 

Close-pollination,  134. 

Clotbur,  169,  230,  436,  Fig.  555. 

Clover,  4,  7,  68,  221,  249,  251,  382,  Figs. 
187,  527;  bracts,  110,  Fig.  173;  chloro- 
phyll, 83;  inflorescence,  120;  roots, 
nodules  on,  7S;  sleep  of,  49,  Fig.  85; 
pollination,  137. 

Cobea,  115. 

Cockle,  242,  354. 

Coco-grass,  244. 

Coffee,  135,  Fig.  201;  tree,  100. 

Cohosh,  anther,  271. 

Coleus,  75,  287;  chlorophyll,  84;  cuttings, 
23,  25,  26;  cells,  265;  starch  in,  86. 

Collateral,  288. 

Collection,  making  a,  279. 

Collenchyma,  280. 

Coilinsia,  406. 

Collodion,  303,  Fig.  476. 

Colonies,  230. 

Color  of  foliage,  233. 

Coltsfoot,  442. 

Columbine,  358,  Fig.  517;  fruit,  157. 

Columella,  188. 

Column:  body  formed  of  union  of  sta- 
mens and  pistil  in  orchids,  (300). 

Columnar  trees,  64,  Fig.  112. 

Commelina,  334.    Commelinaoeae,  334. 

Companion  cells,  280. 

Compass  plant,  50,  297. 

Complete  flower:  all  parts  present,  (273). 

Complete  leaf:  having  blade,  petiole, 
stipules,   (206),  Fig.  145. 

Composite,   150,  431. 

Corr.positous  flowers,  150. 

Compound  leaves,  95. 

Compound  pistil:  of  more  than  one  car- 
pel united,  (271) 

Concentric,  288. 

Cone-flower,  438. 

Conical  trees,  64. 

Coniferse,  271,  324. 

Conjugation,  186. 


INDEX    AND     GLOSSARY 


451 


Connate,  97,  Fig.  148. 

Convallaria,  334. 

Convolvulacese,  411. 

Convolvulus,  412;  family,  411. 

Coral  root,  90,  93,  Fig.  132. 

Corallorhiza,  Fig.  132. 

Cordate:  heart-shaped,  (211). 

( loreopsis,  440. 

Cork  oak,  294. 

Corm:  a  solid  bulb-like  part,  (82). 

Cormel:  a  corm  arising  from  a  mother 
corm,  (82). 

Cormlet:  aerial  corm,  (82). 

Corn,  8,  11,  139,  212,  213,  250,  254,  271, 
279,  285,  Figs.  14,  230,  231,  427,  448, 
452,  454;  ash  in,  77;  broom,  139,  250, 
Figs.  233,  429;  field,  221,  227,  Fig.  385; 
germination,  133,  134,  135,  171,  173, 
175,  178,  Figs.  317-321,  378;  monoe- 
cious, 139,  Fig.  230;  North  and  South, 
212,  Fig.  378;  phyllotaxy,  48;  roots,  7, 
296;  stalk,  17;  starch,  274,  275;  stems, 
267;  stomates,  301;  syrup,  272;  trans- 
piration in,  81;  water  in,  76;  wilting,  81; 
as  weed,  241. 

Corn-cockle,  Fig.  181. 

Corn-flower,  442;  flowers,  151,  Figs.  256, 
559. 

Corolla:  inner  circle  of  floral  envelopes, 
(265). 

Corpse  plant,  425. 

Corydalis,  364. 

Corymb:  short  and  broad,  more  or  less 
flat-topped, indeterminate  cluster,  (254), 
Figs.  192,  193,  197. 

Corymbose  inflorescence:  outer  flowers 
opening   first;  indeterminate,    (248). 

Cosmos,  437. 

Cotton,  67,  147,  148,  249,  251,  271,  Fig. 
115;  fibers,  263. 

Cotyledon:  seed-leaf,   (332). 

Couch-grass,  Fig.  27. 

Cowpea,  251,  384,  Figs.  273,  532;  nodules 
on  root,  78. 

Cowslip,  358,  422. 

Crab-apple,  391. 

Cranberry,  424;  high-bush,  429. 

Cranesbill,  373. 

Cratsegus,  392. 

Creeper:  a  trailing  shoot  which  takes 
root  throughout  its  length,  (56). 

Creeping  stems,  14,  Fig.  18. 

Crenate:  shallowly  round-toothed,  (212). 

Cress,  fruit,  160;  winter,  366. 

Crinkle-root,  367. 

Crocus,  4,  34,  35.  338,  Figs.  52,  53.  497. 

Crops,  249. 

Cross-fertilization:  secured  by  pollen 
from  another  flower,  (278). 

Cross-pollination:  transfer  of  pollen  from 
flower  to  flower,  (278). 


Crowfoot,  357;  family,  355. 

Crown:  that  part  of  the  stem  at  the  sur- 
face of  the  ground,  'v37);  -tuber,  32, 
Fig.  47. 

Cruciferse,  160,  365. 

Cryptogam:  flowerless  plant,  as  fern, 
moss,  fungus,  185,  321,   (353). 

Crystals,   275.     Crystaloids,   275. 

Cucumber,  251,  287;  collenchyma,  280; 
fruit,  162;  pits,  267;  root-pressure,  74; 
squirting,  167,  280;  tendrils,  114. 

Cudweed,  444. 

Cupuliferae,  342. 

Currant,  395,  Figs.  540-542;  bud.  Fig. 
58;  cuttings,  23,  26,  Fig.  40;  fruit,  160; 
stem,  294,  Fig.  465. 

Cuscuta,  412,  Fig.  553. 

Cutting:  severed  piece  of  a  plant  designed 
to  propagate  the  plant,  (51),  (61), 
Figs.  29,  33-41;  hardwood,  26;  soft- 
wood, 23. 

Cutting-bed,  25,  Fig.  36. 

Cutting-box,  25,  29. 

Cutting  sections,  303. 

Cycas,  301. 

Cyclamen,  265,  423. 

Cycloloma,  170. 

Cyclone  plant,  170. 

Cydonia,  391. 

Cyme:  broad,  more  or  less  flat-topped, 
determinate  cluster,  (257),  Figs.  196, 
199. 

Cymose  inflorescence:  central  flowers 
opening  first;  determinate,  (256),  Fig. 
195. 

Cynoglossum,  413. 

Cypress,  swamp,  Fig.  435;  vine,  411,  Fig. 
551. 

Cypripedium,  340. 

Cystolith,  276. 

Cytoplasm,  263. 

Daffodil,  336, 

Dahlia,  33,  271,  437;  double,  151,  153, 

Fig.  257,  258. 
Daisy,  242,  244,  439;  flowers,  150;  ox-eye, 

438,  Fig.  189;  rays,  143;  English,  scape, 

125,  Fig.  200. 
Dalibarda,  140. 
Dandelion,  3,  7,   13,  241,  242,  246,  434, 

Figs.   8,   275;   flowers,    150;   rays,    151; 

scape,  125;  seeds,  168,  Fig.  302;  tissue, 

283. 
Darwin,  quoted,  221,  240. 
Darwinism,  240. 
Date,  seed,  271. 
Datura,  410,  Fig.  275. 
Daucus,  398. 
Day  flower,  334. 

Day-lily,   331,  332,   Figs.   279,  491,  492. 
Deciduous:  falling,  (216). 


452 


INDEX    AND     GLOSSARY 


Decompound,  96. 

Decumbent  stems,  14. 

Decurrent:  running  down  the  stem,  (207), 
Fig.  147. 

Dehiscence:  opening  of  seed-pod  or  an- 
ther, (279),  (312),  159. 

Deliquescent:  trunk  or  leader  lost  in  the 
branches,  (40),  Fig.  17. 

Delphinium,  359. 

Dentaria,  366;  pod,  155,  Fig.  266. 

Dentate:  sharp-toothed,   (212). 

Dependent  plants,  90. 

Dermatogen,  279. 

Desert  vegetation,  Fig.  371. 

Determinate:  definite  cessation  of  growth 
at  the  apex,  (256),  Fig.  195. 

Deutzia,  61,  394. 

Devil's  paint-brush,  436. 

Dewberry,  20,  390,  Figs.  30,  170;  fruit, 
161. 

Dextrin,  271. 

Diadelphous:  in  two  groups,    (297). 

Dianthus,  353,  Fig.  515. 

Dicentra,  364. 

Dichogamy:  stamens  and  pistils  matur- 
ing at  different  times,   (280). 

Diclinous:  imperfect;  having  either  sta- 
mens or  pistils,  (274). 

Dicotyledons,  342. 

Diervilla,  429. 

Digestion:  changing  of  Btarchy  materials 
into  soluble  and  transportable  forms, 
(183). 

Digitalis,  407. 

Digitate,  96,  Figs.  140,  142,  144. 

Dioecious:  staminate  and  pistillate  flow- 
ers on  different  plants,  (284). 

Dispersal  of  seeds,  166. 

Dissecting  apparatus,  132,  Figs.  215-217. 

Divergence  of  character,  221.. 

Divided,  96. 

Dock,  3,  242,  243,  244,  350. 

Dockmackie,  429. 

Dodder,  91,  94,  116,  412,  Fig.  553. 

Dodecatheon,  422. 

Dogbane,  419;  family,  418. 

Dog's-tooth  violet,  330,  Fig.  490. 

Dogwood,  bracts,  110;  osier,  Fig.  5;  tree, 
Fig.  383. 

Dormant  buds,  54,  Fig.  91. 

Double  flowers,  153. 

Dragon-root,  327. 

Dragon's  head,  false,  inflorescence,  Fig. 
185. 

Drupe:  fleshy  one-seeded  indehiscent 
fruit;  stone  fruit,  (320). 

Drupelet:  one  drupe  in  a  fruit  made  up 
of  aggregate  drupes,  (321). 

Dryopteris,  179,  324,  Figs.  331,  332v 

Ducts,  263. 

Dusty  miller,  354. 


Dutch  case-knife  bean,  178. 
Dutchman's  breeches,  364. 
Dutchman's  pipe,  116,  349;  family,  348. 
Dwarf  plants,  212. 

Earth  parasites,  2. 
Echinospermum,  382. 
Echium,  415. 

Ecology:  habits  and  modes  of  life  of  ani- 
mals and  plants,  (397). 
Egg-cell,  133,  187. 
Eggplant,  160,  410,  Fig.  288. 
Eglantine,  390. 
Elaboration,  food,  82. 
Elater,  196. 
Elder,  4,  125,  282,  429;  box,  47,  Fig.  84; 

pith,  263;  poison,  Fig.  422., 
Elecampane,  442. 
Elliptic,  98,  Fig.  151. 
Elm,    14,   64,   218,   222,   287,   346,   Figs. 

507-509;  flower,  130,  143;  foliage,  65; 

fruit,    156;    germination,    178;    phyllo- 

taxy,  47,  48,  Fig.  84;  seed,  168;  shoot, 

history,  57,  58,  Figs.  96-100;  trunk  of, 

65. 
Elodea,  85,  265,  266,  Fig.  439. 
Embryo:  the  plantlet  in  the  seed,   (332). 
Embryology,  106. 
Emersed,  207. 
Emetin,  271. 

Enchanter's  nightshade,  397. 
Endodermis,  279. 
Endogenous  stems,  285. 
Endosperm:  food  in  the  seed  outside  the 

embryo,  (333). 
Entire:  margin  not  indented,  (212). 
Environment:    surroundings;    conditions 

in  which  organisms  grow,  (354),  212. 
Enzymes,  87,  277. 
Eosin  for  staining,  73. 
Epicotyl:  that  part  of  the  caulicle  lying 

above  the  cotyledons,  (340). 
Epidermal  tissue,  279,  283. 
Epidermis  of  leaf,  297. 
Epiga>a,  425. 
Epigeal:    cotyledons   rising   into   the   air 

in  germination,   (339). 
Epigynous:  borne  on  the  ovary,  (307). 
Epilobium,  397. 
Epipactis,  341. 
Epiphyte,  11,  93. 
Equisetaceae,  199.    Equisetum,  199,  202, 

Fig.  369. 
Erect  stems,  14. 
Ericaceae,  423. 
Erigenia,  399. 
Erigeron,  442,  Fig.  560. 
Erythronium,  330,  Fig.  490. 
Eschscholtzia,  362. 
Essential   organs;   stamens   and   pistils, 

(269). 


INDEX     AND    GLOSSARY 


453 


Eupatorium,  444,  Fig.  138. 

Euphorbia,  273,  275,  352. 

Euphorbiacese,  351. 

Eutropic:  in  the  direction  of  the  sun's 
course,  (243),  Fig.  179. 

Evening  primrose,  3,  243,  396,  Figs.  276, 
415. 

Evergreen:  remaining  green,  (216). 

Everlasting,  443. 

Evolution,  240. 

Excurrent:  the  trunk  or  leader  contin- 
ued through  the  top,   (39),  Fig.   19. 

Exogenous  stems,  286. 

Exosmosis,  73. 

Explosive  fruits,  166. 

Exposure,  215. 

Expression  in  plants,  65. 

Fagopyrum,  350,  Fig.  513. 

Fagus,  343. 

Fall  of  leaf,  97,  299. 

False  annual:  perennial  by  means  of  bulbs, 

corms,  or  tubers,  (13). 
Farm  forestry,  258. 
Fastigiate  trees,  64,  Fig.  112. 
Fats,  271,  273. 
Fehling's  solution,  272. 
Fern,  18,  183,  205,  209,  224,  321,  Fig.  479; 

Christmas,    179,    323,    Figs.    331,    332; 

cinnamon,  322,  Fig.  479;  flowering,  322; 

lady,   323;  maidenhair,   180,   Fig.   336; 

marsh  shield,  324;  ostrich,  323;  poly- 

pode,   180,  Figs.  333,  334;  royal,  322; 

sensitive,  322,  323,  Fig.  337;  shield,  324; 

fronds,  179;  in  good  and  poor  light,  42, 

Figs.  73,  74;  discussed,  179,  198,  202; 

prothallus,  180,  Fig.  339. 
Fertilization:  impregnation  of  the  ovule, 

(276). 
Fertilizer,  77. 
Fibrous  tissue,  281. 
Fibro-vascular  bundles,  283. 
Ficus  elastica,  277,  Fig.  447. 
Field  crop,  249. 
Fig,  climbing,  Fig.  78. 
Fig  wort,  406;  family,  404. 
Filament:  stalk  part  of  the  stamen,  (270). 
Filices,  321. 
Film,  moisture,  75. 
Fir,  64. 

Fire-blight,  92. 
Fireweed,  230;  purple,  397. 
Five-finger,  386. 

Flag,  338 ; garden,  299,  Fig.  496 ;  sweet ,  328. 
Flagella.  266. 
Flax,  249,  250,  251,  271. 
Fleabane,  442. 
Fleur-de-lis,  338. 
Flora:  plant  population  of  a  country  or 

plaic;  also  a  book  describing  this  popu- 
lation, (355). 


Floral  envelopes,  127. 

Florets:  individual  flowers  of  composites 

and  grasses,  (303),  Figs.  255-258. 
Floriculture,  250. 
Flower,    parts    of,    127;    -branches,    118; 

-bud,  39;  -cluster,  118;  -stem,  125. 
Foliage,  2,  65,  95. 
Follicle;   dry,  dehiscent  pericarp  opening 

on  the  front  suture,  (314). 
Food  elaboration,  82. 
Food,  reservoirs,  31;  supply  and  variation, 

Forest,  256,  Figs.  387-394,  398. 

Forget-me-not,  414. 

Formalin,  303.    Formic  acid,  271. 

Forms  of  plants,  64. 

Forsythia,  61,  420. 

Foul-gas,  83. 

Foxglove,  407. 

Fragaria,  387,  Figs.  533,  534. 

Framework,  2,  67,  Figs.  3,  4. 

Fraxinus,  421. 

Freesia,  339,  Fig.  498. 

Free-swimming,  207. 

Fringe-tree,  421. 

Frog  spittle,  185. 

Frond:  leaf  of  fern,  (345). 

Fruit-bud,  39,  Figs.  61,  62,  70,  71. 

Fruits,  155. 

Fuchsia,   17,   397;  and  light,  43;  bracts, 

Fig.  172;  cuttings,  25,  26;  flower,  128; 

Fig.  205;  inflorescence,   119,  Fig.   183; 

phyllotaxy,  48;  water-pores,  299. 
Fumariaceae,   363. 
Fumitory,  364. 
Function  of  leaves,  95. 
Function:  what  a  plant  or  a  part  does; 

its  vital  activities. 
Fundamental  tissue,  283. 
Fungi,  91,  183,  1S7,  201,  203,  206,  Figs. 

135,  137. 
Funiculus,  171. 
Funkia,  332,  Figs.  491,  492. 
Funnelform,  144,  Fig.  240. 

Galanthus,  336,  Fig.  495. 

Galium,  426;  climbing,  112. 

Gall,  92. 

Gametophyte,  181,  201. 

Gamopetalae,  400. 

Gamopetalus:  corolla  of  one  piece,  (267), 

Fig.  204. 
Gamosepalous:  calyx  of  one  piece,  (267), 

Fig.  204. 
Gaultheria,  424. 
Gaylussacia,  424. 
Gemmae,  194. 
Generation:  period  from  birth  to  death, 

(8). 
Gentian,  417;  family,  417.    Gentianacese, 

417. 


454 


INDEX    AND    GLOSSARY 


Geraniaceae,  373. 

Geranium,    17,   287,   298,  301,  373,  Figs. 

470,  472;  chlorophyll,  83;  cuttings,  23, 

25,  26,   Figs.   33,   38,   39;  family,  373; 

inflorescence,   Fig.   195;  and  light,  43; 

starch  in,  86. 
Germander,  402. 
Germination,  70,  171,  172. 
Geum,  386. 
Gherkin,  251. 
Gilliflower,  366. 
Gill-over-the-ground,  403. 
Ginger,  18. 
Ginger,  wild,  99,  349. 
Glabrous:  not  hairy. 
Gladiolus,  34,  35,  339,  Figs.  54,  499. 
Glandular,  298. 
Glaucous:  covered  with  a  "bloom"  or  a 

whitish  substance. 
Gleditschia,  381. 
Globe-flower,  390. 
Globoid  inclusions,  275. 
Glomerule:  dense  head-like  cyme,  (257). 
Gloxinia,  leaf-cuttings,  21. 
Glucose,  85,  271,  272. 
Glucoside,  271. 
Glume,  152. 
Gnaphalium,  444. 
Goat's-beard,  434. 
Golden  bell,  61. 

Goldenrod,  3,  150,  232,  233,  442. 
Goober,  141,  251. 
Gooseberry,  160,  395. 
Goose-grass,  426. 
Gourd,  251;  collenchyma,  280. 
Graft:  a  branch   or  bud  made   to  grow 

on    another  plant,   27,    (60),   Figs.   32, 

42-44. 
Grafting-wax,  29. 
Grape,  282;  cane,  Fig.  460;  crystals,  275, 

276;  cuttings,   23,   26;  fruit,   160,   Fig. 

176;  hyacinth,  331;  leaves,   100;  root, 

Fig.  467;  sugar,  272;  tendrils,  114,  117, 

Fig.    176;   sap-pressure,    74;   sympode. 

Fig.  180. 
Grass,    17,   231,   232,   249;   flowers,    151; 

blue-eyed,  338;  leaf,  Fig.   150;  family, 

152;  pink,  342. 
Grasses,  285;  leaves  of,  98,   102;  phyllo- 

taxy,  49;  pollination,  138;  roots  of,  7; 

starch,  274. 
Grass  of  Parnassus,  394. 
Gratiola,  407. 
Greek  valerian,  417. 
Greenbrier,  tendril,  115;  stem,  285. 
Gromwell,  414. 
Ground  cherry,  409. 
Ground  ivy,  403. 
Ground-nut,  385. 
Guinea  squash,  410. 
Gum-resin,  271,  273. 


Gymnosperm:  seed  naked  (not  in  an 
ovary);  applied  to  pines,  spruces,  etc., 
(326),  324. 

Habenaria,  341. 

Habitat:  particular  place  in  which  a  plant 

grows,  (355). 
Habit:    the    looks,    appearance,    general 

style  of  growth,  (36). 
Hackberry,  347. 
Hair-grass,  170. 
Hairs,  298. 

Halophytic  societies,  228. 
Harbinger  of  spring,  399. 
Hardhack,  392. 
Hardwood  cutting,  26. 
Harebell,  430. 
Haustoria,  91,  Fig.  137. 
Hawkweed,  244,  436. 
Hawthorn,  108,  392;  -pear  graft,  27. 
Hazel,   138. 

Head  of  tree,  form  of,  65. 
Head:    short,    dense    spike,    (251),    Figs. 

187,  188,  197. 
Heart-seed,  376. 
Heart's-ease,  369. 
Heath,  93;  family,  423. 
Hedeoma,  401. 

Hedera  helix,  277,  287,  300,  Fig.  468. 
Hedge  hyssop,  407. 
Helianthus,  439. 

Heliotrope,  413.    Heliotropium,  413. 
Heliotropism:   turning  toward   the  light, 

(101). 
Hematoxylin,  266,  303. 
Hemerocallis,  331. 
Hemlock,  213,  271,  Fig.  484;  poison,  247; 

water,  247. 
Hemp,  249,  251,  348. 
Henna  root,  273. 
Hepatica,  156,  233,  356. 
Herb,  3. 
Herbaceous:  not  woody,  (11);  perennial, 

3. 
Herbarium,  311,  Fig.  478. 
Herb  Robert,  374. 
Herbicides,  246. 
Heredity,  239. 
Hetercecism,  192. 
Hibiscus,  62,  Fig.  152. 
Hickory,  50,  155;  bud,  39,  111,  Figs.  63, 

64,  87;  inflorescence,  121;  leaf-scars,  37; 

monoecious,  138. 
Hieracium,  436. 
Hilum,  or  seed-scar,  171. 
Hip:  fruit  of  the  rose,  (323),  Fig.  292. 
Hobblebush,  429. 
Hog-peanut,  140,  Fig.  238. 
Hollyhock,    4,     372;     flower,    136,    147, 

148,    153,  Figs.    222,    223,    263;    cells. 

265. 


INDEX     AND     GLOSSARY 


455 


Holly,  phyllotaxy,  48;  tree.  Fig  380; 
stomates,  299. 

Honesty  fruit,  160. 

Honey  locust,  381;  buds,  37;  leaf,  100; 
thorns,  108;  tree,  Fig.  117. 

Honeysuckle,  62,  428,  Fig.  554;  buds,  :<7; 
family,  427;  leaves,  Fig.  148;  phyllo- 
taxy,  48;  swamp,  425;  Tartarian,  37, 
53;  twiner,   115. 

Hop,  115,  116,  251,  348,  Fig.  179. 

Hop  clover,  383. 

Horehound,  403. 

Horse-chestnut,  377;  bud,  30,  111;  fruit, 
Fig.  277;  germination,  178;  inflores- 
cence, 123;  leaf,  99;  leaf -scar,  37. 

Horse-mint,  400. 

Horse-radish,  3G7. 

Horsetails,  199,  Fig.  309. 

Horse-weed,  443,  Fig.  560. 

Horticultural  crop,  249. 

Host,  78,  91. 

Hound's  tongue,  169,  243,  413. 

House-leek,  20;  phyllotaxy,  48. 

Houstonia,  427. 

Huckleberry,  424;  anther,  135. 

Humulus,  348. 

Humus,  210. 

Hyacinth,  35,  331;  crystals,  276;  grape, 
331;  inflorescence,  Fig.  186;  scape,  125. 

Hydrangea,  62,  125,  131,  394;  doubling, 
153. 

Hydrogen,  76,  82. 

Hydrophyllace®,  415. 

Hydrophytic   society,    228,    Fig.    395. 

Hyperieacea;,  370. 

Hypericum,  371. 

Hyphse,  91,  188. 

Hypoeotyl:  that  part  of  the  caulicle 
lying  below  the  cotyledons,  (338). 

Hypogeal:  cotyledons  remaining  beneath 
the  ground  in  germination,   (339). 

Hypogynous:  borne  on  the  torus,  or  un- 
der the  ovary,   (307). 

Hypoxis   337 

Iberis,  368. 

Immersed,  207. 

Impatiens,  375;  collenchyma,  Figs.  449, 

521,  522;  water-pores,  299,  301;  seeds, 

166. 
Imperfect  flower:  having  either  stamens 

or  pistils,   (274). 
Inclusions,  275. 

Indehiscent:  not  opening,  (312). 
Independent  plants,  90. 
Indeterminate:  growing  on  from  the  apex, 

(248). 
Indian  hemp,  419. 
Indian  pink,  431. 
Indian  pipe,  90,  425. 
Indian  tobacco,  431, 


Indian  turnip,  149,  327. 

India-rubber   plant,   271,   276,   297,   Fig. 

447. 
India  wheat,  350. 
Indigo,  271;  false,  383. 
Indusium,  179,  Fig.  338. 
Inferior,  152. 
Inflorescence:    mode    of    flower-bearing; 

less  properly,  a  flower-cluster,  (260). 
Innocence,  406. 

Insects  and  flowers,  136,  Fig.  227. 
Inula,  442.    Inulin,  271. 
Involucre:    a    whorl    of   small    leaves   or 

bracts    standing    close    underneath    a 

flower  or  flower-cluster,  (299). 
Iodine  test  for  starch,  86,  274. 
Ipecac,  271. 

Ipomoea,  411,  Figs.  551,  552. 
Iridacea?,  337. 
Iris,  338,  Fig.  496;  cells,  265;  family,  337; 

leaf,  297;  stems,  285. 
Iron,  76. 
Ironweed,  445. 
Irregular  flower:  some  parts  in  one  series 

different,    (275). 
Irrigation,  215. 
Isoetes,  200,  202,  Fig.  370. 
Ivy,  10,  100,  113,  277,  287,  292,  297,  299, 

300,  Figs.  174,  468,  471;  Boston,  100, 

113,   Fig.    155;    Kenilworth,   405;   Fig. 

545;  poison,  11,  113,  247,  Fig.  421. 

Jack-in-the-pulpit,  149,  276,  327,  Fig.  251. 

Jacob's  ladder,  417. 

Jamestown-weed,  410. 

Japan  quince,  97,  392. 

Japan  rose,  390. 

Jeffersonia,  360. 

Jerusalem  artichoke,  439. 

Jewel-weed,  166,  230,  280,  375,  Figs.  449, 

521,  522. 
Jimson-weed,  243,  410,  Fig.  275. 
Joe  Pye  weed,  444. 
Johnny-jump-up,  369. 
Johnson-grass,  244. 
Jonquil,  336. 
Judas  tree,  381. 
Juncberry,  391;  and  birds,  168. 
June-grass,  241. 
Juniper,  164,  326. 

Kafir,  139,  250,  Fig.  234. 

Kale,  251. 

Kalmia,  425. 

Karyokinesis:  indirect  division  or  trans- 
formation of  the  nucleus,  being  one 
means  of  cell  multiplication;  mitosis, 
269,  (4  IS). 

Kentucky  coffee  tree,  100. 

Kerria,  390. 

Key-fruit,  156. 


456 


INDEX     AND     GLOSSARY 


Kinghead,  243. 

Knotweed,  130,  143,  351,  Fig.  210. 

Kohlrabi,  33,  251,  Fig.  48. 

Labiatse,  144,  400.    Labiate,  144. 
Laboratory     advice,     301;     table,     Fig. 

477. 
Lactuca,  435. 

Lady's-slipper,  148,  340,  Fig.  250. 
Ladies'  tresses,  341. 
Lady's  thumb,  351,  Fig.  514. 
Lake-cress,  21. 
Lambkill,  425. 
Lanceolate,  99. 
Landscape  and  plants,  210. 
Lappula,  413. 
Larch,    326,    Figs.    462,    463;    European, 

326. 
Larix,  326. 
Larkspur,  4,  359;  flower,   137,   Figs.  224- 

226;  fruit,  157,  Figs.  269,  270. 
Lateral  flowers,  119,  Fig.  182. 
Lathyrus,  263,  381. 
Laticiferous  tissue,  282. 
Laurel,  425. 

Layer:  a  branch   which   takes   root   and 
gives   rise   to    an    independent    plant, 
(55). 
Layers  of  branches,  56,  Figs.  93,  94. 
Leaf,  bud,  39,  Figs.  70,  71;  -cutting,  21, 
27,  Fig.  41 ;  fall  of,  299 ;  how  to  tell,  103 ; 
-spot,  92;  parts  of,  97. 
Leaflet:  one   part   in    a    compound    leaf, 

(204). 
Leaf-scars,  37,  300,  Fig.  57. 
Leaves,  arrangement  of,  47;  fall  of,  299; 
general  account,  95;  polar,  50;  propa- 
gation by,  21;  sleep  of,  49;  structure, 
297. 
Legume:  simple    pericarp    dehiscing    on 

•both  sutures,  (315). 
Leguminosae,  78,  146,  157,  379. 
Lemon,  acid,  271. 
Lens,    132,    248;    stand    for,    Figs.    214, 

425. 
Lenticels,  294. 
Leonurus,  403. 
Lepidium,  368. 
Lespedeza,  251. 
Lettuce,   435;    wild,    50,    243,    435,    Fig. 

86. 
Leucojum  vernum,  337. 
Liatris,  444. 

Lichen,  94,  183,  193,  209,  Fig.  373. 
Licorice,  wild,  426. 
Life-history:  sum   of   the   events   in   the 

life  of  a  plant,  (7). 
Light   and  plants,   42,   223,  Figs.  73-78, 

81-85. 
Ligneous:  woody,  (11), 
Lignin,  266, 


Ligule  of  isoetes,  201. 
Ligustrum,  421. 

Lilac,  4,  61,  420,  Fig.  72;  bud,  111;  inflo- 
rescence, 125;  phyllotaxy,  48;  stomates, 
299. 
Liliacese,  145,  146,  328. 

Lilium,  329,  Figs.  488,  489. 

Lily,  4,  20,  329,  Figs.  48S,  489;  bulb,  33; 
calla,  1328,  Fig.  486;  day-,  331,  332, 
Figs.  279,  491,492;  Easter,  330;  family, 
328;  germination,  133;  leaves,  102; 
stomates,  301;  tiger,  21,  33,  330,  Fig. 
31;  straw,  332;  Turk's-cap,  330,  Fig. 
489;  water-,  3,  98,  205,  207,  361;  wild 
orange-red,  330;  wood,  330. 

Lily-of-the-valley,  18,  334. 

Linaria,  405,  Figs.  544,  545. 

Linear,  98,  Fig.  150. 

Linnaeus,  308. 

Lipped,  144. 

Lithospermum,  414. 

Liverleaf,  356.    Liverworts,  193,  201. 

Lobed.  96,  100,  Fig.  143. 

Lobelia,  431;  family,  431.  Lobeliaceae, 
431, 

Locule:  compartment  of  a  pistil,  (310). 

Loculicidal:  dehiscence  between  the  par- 
titions, (317). 

Locust,  380;  buds,  37;  honey,  tree,  Fig. 
117;  prickles,  109;  seed,  166;  sleep  of, 
49;  thorns,  108. 

Lodicule,  152. 

Lonicera,  428,  Fig.  554. 

Loosestrife,  423. 

Loquat,  251. 

Lotus,  starch,  274. 

Lucerne,  383,  Fig.  529. 

Lungwort,  414. 

Lupine,  384. 

Lupinus,  384. 

Lychnis,  354. 

Lycopersicum,  410. 

Lycopus,  400. 

Lysimachia,  423. 

Madura,  347. 

Macrospore,  182. 

Madder  family,  426. 

Magnesium,  76. 

Maianthemum,  333. 

Maidenhair,  180,  323,  Fig.  336. 

Maize,  3,  8,   11,  48,   139,   152,   171,   175, 

250,  Figs.  9,  14,  230,  231,  317-321. 
Malic  acid,  271. 
Mallow,    147,    148,    244,    372,    Fig.    248; 

family,  372. 
Maltose.  272. 
Malva,  372. 
Malvaceae,  148,  372. 
Mandrake,  18,  361. 
Mangrove,  12,  20,  Fig.  16. 


INDEX     AND     GLOSSARY 


457 


Maple,  14,  47,  64,  67,  218,  241,  273,  376, 

Figs.  79,  80,  523-526;  branching,  56; 

buds,  37,  39,  40,  41,  ill;  family,  375; 

flowering,  373;   foliage,  65;  fruit,    156; 

germination,   178,  Figs.  323-330;  leaf, 

Figs.  143, 157;  leaf-scar,  37;  phyllotaxy, 

48;  sap-pressure,  74;  seed,  168;  trunk, 

65. 
Marchantia,    193,    197,   202,    Figs.    358- 

364. 
Mare's-tail,  443,  Fig.  560. 
Marigold,  marsh,  358;  pot,  438. 
Marrubium,  403. 
Marsh-cress,  :il>7. 
Marsh  mallow,  148,  372. 
Marsh  marigold,  358. 
Matthiola,  366. 

May-apple,  18,  22,  361;  anther,  135. 
Mayflower,  356,  425 
Maypop,  Ui2, 

Mayweed,  230,  243,  438,  Fig.  417. 
Meadow  grass,  3. 
Meadow  rue,  357. 
Meadow-sweet,  392. 
Medicago,  383,  Fig.  529. 
Medick,  383. 
Medlar,  251. 

Medullary  rays,  278,  286. 
Melilotus,  3S3,  Fig.  52S. 
Melon,  251;  fruit,  162;  tendrils,  114. 
Menispermum,  stem,  287,  289,  294. 
Mentha,  401,  Fig.  543. 
Meristematic,  278. 
Mermaid-weed,  208. 
Mertensia,  414. 
Mesophyll,  272,  297. 
Mesophytic  society,  228,  Fig.  396. 
Micropyle,  171. 
Microscope,  slides,  Fig.  476. 
Microspore,  182. 
Microtome,  303. 
Midrib,  96,  98. 

Mignonette,  inflorescence,  120. 
Mildew,  91,  189,  190,  Figs.  348-351. 
Milk  thistle,  435. 
Milkweed,   418;   family,   417;   fruit,    157, 

Fig.  271;  seeds,   168,  Fig.  303;  tissue, 

283. 
Milkwort,  378;  family,  378. 
Millet,  152,  250,  Fig.  162. 
Milo,  Fig.  234. 
Mimulus,   1(17,  Fig.  546. 
Mineral  nutrients,  69,  75. 
Mint,  401;  family,  400;  phyllotaxy,  48. 
Mistletoe,  93,  94,  299. 
Mitchella,  427. 
Mitella,  394. 
Mitosis,  269. 

Mitrewort,  394;  lalse,  393. 
Mixed  buds,  40;  flower-clusters,  123. 
Moccasin  flower,  340. 


Mock  orange,  62,  395. 

Mock  pennyroyal,  401. 

Monadelphous:  in  one  group,  (297). 

Moneywort,  423. 

Monkey-flower,  407,  Fig.  546. 

Monocotyledons,  102,  327. 

Monoecious:     staminate     and     pistillate 

flowers  on  the  same  plant,  (284). 
Monopodial:  axial  growth  continued  by 

growth   from   terminal    bud   or  persis- 
tence of  the  leader,  117. 
Monotropa,  425. 
Moonflower,  115,  411,  Fig.  552. 
Moonseed,  stem,  2S7,  292,  Figs.  455-457. 
Moose-wood,  377. 
Morning-glory,  15,  411,  412;  family,  94; 

flower,  144,  Fig.  240;  twiner,  115,  116. 
Morphin,  271. 
Morphology,  105. 
Morus,  347,  Fig.  511. 
Mosses,  94,  183,  196,  201,  209,  234. 
Motherwort,  403. 
Mold,  90,  187,  188. 
Mountain-ash,  391. 
Mounting  sections,  303. 
Mucilage,  271. 
Muck,  210. 

Mucor,  188,  Figs.  344-347. 
Mulberry,    flowering,    3S9;    leaves,    100; 

shoot,   Fig.  88;  white,  348,   Fig.   511; 

wild,  347.       • 
Mullein,  3,  15,  243,  405,  Fig.  22;  hairs, 

29S;  inflorescence,  120;  leaf,  Fig.  147; 

pink,  354. 
Muscari,  331. 
Muscus,  271. 
Mushroom,  90,  187,  247,  249,  Figs    133, 

134,  419,  420. 
Muskmelon  seedlings,  Fig.  156. 
Musquash-root,  247. 
Mustard,   243,   247,   251,   365,   Fig.    518; 

family,  365;  fruit,  160;  inclusions,  275; 

pod,    155. 
Mycelium:  vegetative  part  of  a  fungus, 

(194),  188,  Fig.  137. 
Mycorrhiza,  93,  Fig.  132. 
Myosotis,  414. 
Myrtle,  419. 
Myxomycetes,  266. 

Nagelia,  298. 

Naked      flower:     no     floral      envelopes, 

(273). 
Narcissus,  35,  336;  double,  Fig.  491. 
Nasturtium,   374;    flower,   131,   Fig.   211; 

leaf,  Fig.  140;  tendril,  115. 
Natural  selection,  240. 
Nectarine,  237. 
Nectary,  137. 

Needle  for  dissecting,  132,  Fig.  215. 
Nepeta,  403. 


458 


INDEX    AND    GLOSSARY 


Nerium,  419. 

Netted-veined,  95. 

Nettle,  230,    348;   acid,   271;    cells,    265; 

family,  345. 
Nettle-tree,  347. 
Nicotiana,  411,  Fig.  550. 
Nicotin,  271. 

Nightshade,  276,  409;  family,  408. 
Nine-bark  fruit,  157. 
Nitella,  266. 
Nitrogen,  76,  82,  249. 
Node:   a  joint;   the   space   between   two 

joints  is  an  internode. 
Nodules,  78,  Figs.  126,  127. 
Nucleolus,  264. 
Nucleus,  186,  263. 
Nut-grass,  244. 
Nutrient,  water  as,  76. 
Nux  vomica,  271. 
Nymphsaceffi,  361. 

Oak,  14,  93,  233,  271,  286,  287,  343,  Figs. 
500-506;  branching,  56;  -chestnut 
graft,  28;  expression  in,  66;  family, 
342;  inflorescence,  121,  Fig.  228;  mon- 
oecious, 138;  poison,  248,  Fig.  423; 
transpiration  in,  70;  where  grows, 
207. 

Oakesia,  332. 

Oats,  250,  Fig.  426;  inflorescence,  121, 
152,  Fig.  191;  lodged,  Fig.  382;  roots, 
7;  seed,  172;  starch,  274,  275. 

Oblong,  98,  Fig.  149. 

Obovate,  99. 

Obtuse:  blunt,  (211). 

CEcology:  see  ecology. 

CEnothera,  396. 

Offset:  a  plant  arising  close  to  the  base 
of  the  mother  plant,  (56). 

Oils,  271,  273. 

Okra,  148. 

Old-hen-and-chickens,  20. 

Old-man  vine,  359. 

Oleacese,  420. 

Oleander,  419;  leaf,  297. 

Olericulture,  250. 

Olive,  family,  420;  fruit,  161. 

Onagraceee,  397. 

Onion,  4,  271,  276,  277;  bulb,  33,  34,  35, 
Figs.  49-51;  cells,  264;  germination, 
178. 

Onoclea,  322. 

Oogonia,  187. 

Oospore,  187. 

Operculum,  198. 

Ophioglossaceae,  198. 

Ophioglossum,  198,  Fig.  368. 

Opium,  poppy,  271. 

Opposite  leaves,  47. 

Orange,  mock,  62,  395;  osage,  48,  108, 
347,  Fig.  510, 


Orbicular,  99,  Fig.  153. 

Orchid,  271,  341;  epiphytes,  11,  94;  fam- 
ily, 339;  flowers,  143,  148,  Fig.  250: 
leaves,  102;  roots,  Fig.  13;  stems,  285. 

Orchidaceae,  339. 

Orchis,  341. 

Ornithogalum,  331. 

Osage  orange,  48,  108,  347,  Fig.  510: 
phyllotaxy,  48. 

Osier,  4;  dogwood,  Fig.  5. 

Osmorrhiza,  399. 

Osmosis,  71,  Figs.  123,  124.  Osmotic 
pressure,  72. 

Osmunda,  322,  Fig.  479. 

Oswego  tea,  400. 

Ovary:  seed-bearing  part  of  a  pistil, 
(272),  Fig.  209. 

Ovate,  99,  Fig.  152. 

Overgrowth,  232. 

Oxalic  acid,  271. 

Oxalis,  49,  166,  374,  Fig.  300. 

Ox-eye  daisy,  438,  Fig.  189. 

Oxygen,  76;  liberation  of,  77,  Fig.   130. 

Oyster  plant,  434. 

Pseonia,  358. 

Paint-brush,  244. 

Painted  cup,  407. 

Palet,  152. 

Palisade  cells,  297. 

Palisades  of  Hudson,  Fig.  372. 

Palm,  15,  65,  Fig.  113;  choked  by  fig, 
Fig.  78. 

Palma  Christi,  352. 

Palmate,  96,  Fig.  140. 

Panicle:  branching  raceme,  (253). 

Panicum,  170. 

Pansy,  370;  flower,  Fig.  212. 

Papaver,  271,  362.     Papaverace®,  362. 

Paper  bamboo,  forest,  Fig.  437. 

Papilionaceous  flowers,  146,  Fig.  245. 

Pappus:  peculiar  calyx  of  composites, 
(304). 

Paraffin,  303. 

Parallel-veined,  95. 

Paraphyse,  197. 

Parasite,  90,  200,  Figs.  131,  136;  vs. 
graft,  22. 

Parenchyma,  266,  278,  297. 

Parnassia,  394. 

Parsley,  121,  399;  family,  397. 

Parsnip,  3,  33,  121,  398. 

Parted,  96. 

Partridge-berry,  427. 

Passion  flower,  162. 

Pastinaca,  398. 

Pea,  3,  79,  97,  247,  250,  381,  Fig.  426; 
black,  384,  Fig.  532;  everlasting,  166, 
381,  Fig.  272;  experiment  in  respira- 
tion, 89;  flowers,  146,  Fig.  206;  germi- 
nation,  171,   173,   174,   178,  Fig.   322; 


INDEX    AND     GLOSSARY 


459 


legume,  157;  nodules  on  root,  78;  pistil, 
129,  Fig.  200;  stock,  384,  Fig.  532; 
sweet,  254,  263,  381,  Fig.  245;  tendril, 
114,   Fig.  177. 

Peach,  2,  32,  251,  271,  287,  387,  388, 
Figs.  105,  431,  476,  535;  bud,  37,  3!), 
40,  41;  crystals,  276;  fruit,  161;  foliage, 
65;  family,  379;  inclusions,  275;  leaf, 
99;  phyllotaxy,  48;  and  nectarine,  237; 
pruning,  Figs.  103,  105,  108. 

Peanut,  141,  157,  251,  Figs.  237,  238, 
274,  430. 

Pear,  251,  272,  391;  bud,  36,  39,  40, 
111,  Figs.  56,  61,  62,  65-67,  70;  dis- 
eases of,  92;  fruit,  162,  266,  Fig.  293; 
form  of,  68,  Figs.  118,  119;  inflo- 
rescence, 123,  Fig.  196;  leaf-scar,  37; 
phyllotaxy,  48;  -quince  graft,  27; 
sclerenchyma,  282;  thorns,  108. 

Peat,  210. 

Pedicel:  stem  of  one  flower  in  a  cluster, 
(261). 

Peduncle:  stem  of  a  flower-cluster  or  of  a 
solitary  flower,  (261). 

Pelargonium,  374. 

Peltate:  attached  to  its  stalk  inside  the 
margin,  (209),  Figs.  135,  140. 

Pentamerous:  in  5's,  (291). 

Pentstemon,  406. 

Peony,  358;  fruit,  157;  stomates,  299. 

Pepo:  fruit  of  pumpkin,  squash,  etc., (325). 

Pepper-grass,  243,  368. 

Pepper,  red,  4,  410,  Fig.  547. 

Peppermint,  401. 

Pepper-root,  367. 

Perennial:  of  three  or  more  seasons' 
duration,  (10). 

Perianth:  floral  envelopes  of  lily-like 
plants  (more  properly  of  monocoty- 
ledonous  plants),  (295). 

Periblem,  279. 

Pericarp:  ripened  ovary,  (311). 

Periohetia,  197. 

Per igy nous:  borne  around  the  ovary, 
(306). 

Peristome,  198. 

Perithecium,  190. 

Periwinkle,  419. 

Persimmon,  271. 

Persistent:  remaining  attached,  (216). 

Personate,  145,  Fig.  243. 

Peruvian  bark,  271. 

Petal:  one  of  the  separate  leaves  of  a 
corolla.  (266),  Fig.  209. 

Petiole:  leaf-stalk,  (206). 

Pctiolule:  stalk  of  a  leaflet,  (208). 

Petunia,  410,  Figs.  548,  549. 

Phaseolus,  384,  Figs.  530,  531. 

Phellogen,  293. 

Phenogam:  seed-bearing  or  flowering 
plant,  (353),  324. 


Philadelphia,  395. 

Phloem,  283. 

Phlox,  144,  233,  416,  Fig.  241;  family, 
416. 

Phosphorus,  76. 

Photosynthesis:  the  making  of  organic 
matter  from  CO2  and  water,  in  the 
presence  of  light,  (177,  178). 

Phyllodium:  leaf-like  petiole,  (226),  Fig. 
163. 

Phyllotaxy:  arrangement  of  leaves  and 
flowers  on  the  stem,  (112). 

Physalis,  409. 

Physostegia,  inflorescence,  Fig.  185. 

Picea,  325,  Fig.  483. 

Pie-plant,  350. 

Pigeon-grass,  243. 

Pigweed,  3,  67,  239,  242,  243,  Figs. 
406,  408,  411. 

Pine,  15,  93,  162,  232,  249,  281,  394,  Figs. 
10,  19,  421-423,  451,  462,  481',  482;  and 
cone,  Fig.  299;  foliage,  Fig.  158;  ger- 
mination, 171;  and  light,  44;  needles, 
102;  pollination,  138;  shoot,  Fin.  L58; 
stem,  Figs.  461,  466;  trees.  Figs.  388, 
390;  wood  structure,  267,  Fig.  440. 

Pine-sap,  425,  426. 

Piney,  258. 

Pink,  4,  159,  353;  family,  353;  fire,  354; 
grass,  342;  wild,  354. 

Pinna?,  321.    Pinnules,  321. 

Pinnate,  95,  Fig.  141. 

Pinnatifid,  97. 

Pinus,  324,  Figs.  481,  482. 

Pinxter  flower,  425. 

Pistil:  ovule-bearing  or  seed-bearing  or- 
gan, (271),  Figs.  206-209. 

Pistillate:  having  pistils  and  no  stamens, 
(274),  Figs.  190,  229,  230. 

Pisum,  381. 

Pitchforks,  440,  Fig.  558. 

Pits,  267. 

Plane  tree,  leaf-scar,  Fig.  474. 

Plankton,  207. 

Plantain,  243,  inflorescence,  120. 

Plant-breeding,  240. 

Plant-food,  defined,  69. 

Plant  society,  228. 

Plastid,  263,  264. 

Plerome,  279. 

Pleurisy  root,  418. 

Plum,  20.  251,  254,  387,  388,  Figs.  537, 
538;  blossom,  162,  Fig.  209;  bud,  39; 
drupe,    161,    Fig.   2S9;   phyllotaxy.    IS; 

pollination,  Pig.  218;  thorns,  108. 

Plumule:  bud  in  the  embryo,  (332). 
Plur-annual:    of    one    season's    duration 

beoause  killed  by  frost,  (14). 
Pod:  dehiscent  pericarp,  (312). 
Podophyllum,  361. 
Pogonia,  342. 


460 


INI>EX    AND     GLOSSARY 


Poinsettia,  352;  bracts,  110;  starch,  273, 

274. 
Poisonous  plants,  247. 
Polarity,  50. 
Polemoniacese,  416. 
Polianthea,  337. 
Pollards,  56,  Fig.  92. 
Pollen  germinating,  Figs.  218,  219. 
Pollen:    spores    borne    by    the    stamen, 

(270),  133,  Figs.  218,  219. 
Pollination:  transfer  of  pollen  from  sta- 
men to  pistil,  (278). 
Pollinium :  pollen  in  a  coherent  mass,  (301 ). 
Polyanthus,  422. 
Polygalacese,  378. 
Polygonacea,  349. 
Polygonatum,  334. 

Polygonum,  351,  Fig.  514;  climbing,  112. 
Polyhedral,  263. 
Polypetalous:  corolla  of  separate  parts  or 

petals,  (267). 
Polypode,  180,  323,  Figs.  333,  334. 
Polypodium,  180,  323. 
Polyporus,  Fig.  135. 
Polysepalous:  calyx  of  separate  parts  or 

sepals,  (267). 
Polystichum,  323. 

Polytrichum  commune,196,  Figs.  365-367. 
Pome:  fruit  of  apple,  pear,  etc.,  (324). 
Pomology,  250. 
Pond-lily,  361. 
Poplar,     231;    bud,     36;     cuttings,     26; 

dioecious,      138;      inflorescence,      121; 

Lombardy,  64;   phyllotaxy,   48;   seeds, 

168. 
Poppy,   326;    family,    362;     opium,   271, 

362. 
Pores,  79,  83,  88. 

Portulaca,  159,  371;  fruit,  Fig.  280. 
Portulacaceee,  371. 
Potassium,  76. 
Potato,  4,  16,  19,  32,  35,  68,  77,  160,  249, 

251,    254,    409,    Fig.    24;    cells,    265; 

cuttings,    23;    flower,    144,    Fig.    242; 

inclusions,  275;  phyllotaxy,  49;  sprouts, 

31,   84,   90,   Fig.   45;   starch,   31,    274, 

275,  Fig.  42;  stem,  287;  sweet,   16,  32, 

Fig.  204;  -tomato  graft,  28. 
Potentilla,  386. 
Pot  marigold,  438. 
Prickles,  109,  Figs.  169,  170. 
Prickly  ash,  109,  Fig.  169. 
Prim,  421. 

Primrose,  422;  family,  422. 
Primula,  298,  422.     Primulacese,  422. 
Prince's  feather,  351. 
Privet,  62,  421. 
Promycelium,  191. 
Propagation    by   buds,    21;    leaves,    21; 

rhizomes,  18;  roots,  19. 
Prosenchyma,  280. 


Proserpinaca,  208. 
Proteids,  271.   Protein,  271. 
Proterandrous:    anthers    maturing    first, 

(280),  Fig.  222. 
Proterogynous:     pistils     maturing    first, 

(280). 
Prothallus,  180,  Fig.  339. 
Protococcus,  263. 
Protonema,  198. 
Protoplasm,  70,  88,  186,  263. 
Prunella,  402. 
Pruning,  59,  60. 
Prunus,  387,  Figs.  535-539. 
Pseud-annual:    perennial    by    means    of 

bulbs,  corms,  or  tubers,  (13). 
Pteridophyte,  183. 
Pteris,  267,  2S9,  323,  Fig.  456. 
Puccinia,  190,  192,  Figs.  352-357. 
Puccoon,  414. 
Pulse  family,  379. 
Pumpkins,    251,    289;   and   collenchyma, 

280;    corn,  221,  Fig.  385;  flower,  144; 

fruit,  162;  germination,  174;  hairs,  298; 

leaf,  100;  roots,  Fig.  121. 
Purslane,  159,  241,  242,  243,  371;  family, 

371. 
Pusley,  371. 

Pussies  of  willow,  121,  Fig.  60. 
Pyrus,  391. 
Pyxis:  pod  opening  around  the  top,  (317), 

Fig.  280. 

Quack-grass,  18,  19,  242,  244,  Fig.  27. 
Quercus,  343,  Figs.  500-506. 
Quillwort,  200. 

Quince,  251,  271,  391;  fruit,  162;  Japa- 
nese, 97;  -pear  graft,  27. 
Quinin,  271. 

Raceme:  simple  elongated  indeterminate 

cluster    with    stalked    flowers,     (249), 

Figs.  184,  197. 
Radicula,  367. 
Radish,  7,  12,  17,  33,  69,  70,  75,  368,  Figs. 

11,   120;  and  light,  43,  Fig.   75;  fruit, 

160. 
Ragweed,  209,  230,  233,  243,  436,  Figs. 

416,  556. 
Ranunculaceffi,  355. 
Ranunculus,  357. 
Rape,  251. 
Raphanus,  368. 
Raphe,  172. 
Raphides,  276. 
Raspberry,  20,  21,  251,  389;  and  birds, 

168;  fruit,  160,  161,  Fig.  290;  leaf,  Fig. 

142;  pruning,  61,  Figs.  106,  107. 
Rattlesnake  plantain,  341. 
Rattlesnake-weed,  436. 
Ray:  outer  modified  florets  of  some  com- 
3,  (305). 


INDE  X     AND     GLOSSARY 


4G1 


Receptacle,  128;  of  liverwort,  194;  of 
moss,  197. 

Receptive  stigma,  134. 

Redbud,  381. 

Redroot,  242,  Figs.  400,  411. 

Regular  flower:  the  parts  in  each  series 
alike,  (275). 

Reinforced  fruit:  other  parts  grown  to 
the  pericarp,  (311),  101. 

Reniform,  09. 

Respiration:  taking  in  O,  giving  off 
C02,  82,  (187);  in  seeds,  173. 

Resting  bud,  30,  01. 

Resting-spore,  186. 

Rheum,  350. 

Rheumatism  root,  360. 

Rhizoid,  186. 

Rhizome:  underground  stem;  rootstock, 
(44),  Figs.  22-24,  27^29;  propaga- 
tion by,  18;  starch  in,  31. 

Rhododendron,  425;  anther,  135. 

Rhodora,  425. 

Rhubarb,  3,  45,  350,  Figs.  81,  82;  bud, 

Rhus,  Figs.  421,  423. 

Ribbon  grass,  86. 

Ribes,  395,  Figs.  540-542. 

Rice,  152,  249,  250;  starch  in,  274,  275. 

Richardia,  328,  Fig.  486. 

Ricinus,  352. 

Rings  of  annual  growth,  111. 

Robinia,  380;  spines,  109. 

Robin's  plantain,  443. 

Rock  cress,  366. 

Root,  2,  7,  69,  Fig.  120;  action,  69;  aerial, 
10,  Figs.  12-14;  climbers,  112,  Fig.  174; 
cutting,  20;  growth,  Figs.  25,  20;  -hairs, 
9,  09,  Figs.  11,  121,  122,  125;  -pressure, 
73,  81;  propagation  by,  19;  structure, 
69,  295;  system,  7;  tubers,  32. 

Rootlets,  69,  Figs.  120,  125. 

Rootstock:  subterranean  stem;  rhizome, 
(44);  propagation  by,  18. 

Rosa,  390. 

Rosaces,  385. 

Rose  acacia,  62,  380. 

Rose,  4,  249,  251,  390;  climbing,  112; 
cutting,  Fig.  35;  family,  385;  hip,  101, 
Fig.  292;  mallow,  373;  -moss,  371,  Fig. 
280;  of  Sharon,  02,  373;  prickles,  109; 
swamp,  390;  variation,  238. 

Rotate,  144,  Fig.  242. 

Round-headed  trees,  64,  Figs.  Ill,  112. 

Rubber,  249. 

Rubiacese,  426. 

Rubus,  389. 

Rudbeckia,  438,  Fig.  557. 

Rue  anemone,  357. 

Rumex,  350,  Fig.  512. 

Runner:  a  trailing  shoot  taking  root  at 
the  nodes,  (56). 


Russian  thistle,  170,  243,  Fig.  114. 
Rust,  91,  190,  Figs.  352-357. 
Rutabaga,  251. 
Rutland  beauty,  412. 
Rye,    249;    flower,    151,    152,    Fig.   260; 
-pollination,  138. 

Sage,  common,  401;  scarlet,  110,  401. 

Salsify,  33,  434. 

Salt-loving  societies,  228. 

Balverform,  114,  Fig.  241. 

Salvia,  401. 

Samara:  indehiscent  winged  pericarp, 
(312). 

Sambucus,  429. 

Sand-dune  plants,  Fig.  397. 

Sanguinaria,  303. 

Sap,  72;  descent  of,  87;  -pressure,  73. 

Saphrophyte,  90,  Figs.  133-135. 

Sapindacea;,  375. 

Saponaria,  354. 

Sassafras,  143. 

Savin,  327. 

Saxifragacea;,  393. 

Saxifrage,  276,  393. 

Scalariform:  with  elongated  mark  ngs, 
(446). 

Scaly  bulb,  33. 

Scape:  leafless  peduncle  arising  from  '.he 
ground,  (262),  Fig.  200. 

Sclerenchyma,  207,  282. 

Sclerotic  tissue,  282. 

Score-card,  254. 

Scramblers,  112. 

Scrophularia,  400. 

Scrophulariaceffi,  404. 

Scutellaria,  402. 

Seaweeds,  181,  185. 

Secondary  thickening,  291. 

Sedges,  leaves,  102. 

Seed,  coats,  171;  dispersal,  166;  dormant, 
2;  starch  in,  31;  -variations,  237. 

Segments,  145. 

Selection,  239. 

Self-fertilization:  secured  by  pollen  from 
same  flower;    close-fertilization,   (278). 

Self-heal,  402. 

Self-pollination:  transfer  of  pollen  from 
stamen  to  pistil  of  same  flower;  close- 
pollination,  (278). 

Seneca  snakeroot,  379. 

Senna,  385. 

Sensitive  fern,  Fig.  437. 

Sepal:  one  of  the  separate  leaves  of 
a  calyx,  (266),  Fig.  209. 

Septicidal:  dehiscence  along  the  parti- 
tions, (317). 

Serrate:  saw-toothed,  (212). 

Service  berry   391 

Sessile:  not  stalked,  (207),  Fig.  201. 

Shadbush,  391. 


462 


INDEX     AND     GLOSSARY 


Shade  and  plants,  223. 

Shadows  in  trees,  66. 

Sharon,  rose  of,  62,  341. 

Sheepberry,  429. 

Shelf  fungus.  Fig.  135. 

Shepherdia,  hairs,  298,  Fig.  469. 

Shepherd's  purse,  242,  368;  capsule,  160, 

Fig.  286. 
Shoot:    a    new    plant    from    root    of   old 

plant,  (53). 
Shooting  star,  422. 
Shrubs:    plants    that    remain    low    and 

produce  shoots  from  base,  (15). 
Sickle-pod,  366. 
Sieve  tissue,  280. 
Silene,  354. 

Silicle:  short  fruit  of  Cruciferse,  (318). 
Silique:  long  fruit  of  Crucifers,  (318). 
Silkweed,  418. 
Silviculture,  257. 
Simple  leaf,  95,  Fig.  138. 
Simple  pistil:  of  one  carpel,   (271),  Fig. 

207. 
Simple  stem,  15,  Fig.  20. 
Sisyrinchium,  338. 
Skullcap,  402. 
Skunk  cabbage,  149,  150,  233,  276,  327, 

Fig.  446. 
Sleep  of  leaves,  49. 
Slips,  23. 
Smartweed,  130,  143,  156,  230,  351,  Fig. 

514. 
Smilacina,  333. 

Smilax  of  florists,  107,  333,  Fig.  493. 
Smilax  tendril,  115. 
Snakehead,  406. 
Snapdragon,  145,  406,  Fig.  243. 
Snowball,     131,     153,     Figs.     264,     265; 

Japanese,  429. 
Snowberry,  Fig.  287. 
Snowdrop,  336,  Fig.  495. 
Snowflake,  337. 
Soapberry  family,  375. 
Soapwort,  354. 
Societies,  228. 
Sod  society,  231,  Fig.  399. 
Softwood  cutting,  23. 
Soil  and  plants,  209,  213. 
Solanaces,  408. 
Solanum,  112,  248. 
Solidago,  442. 

Solitary  flowers,  119,  Fig.  181. 
Solomon's  seal,  18,  334;  false,  333;  two- 
leaved,  333. 
Sonchus,  435. 
Soredia,  193. 
Sorghum,   139,  152,  250,  273,  275,  Figs. 

20,  232-234. 
Sori,  9,  191. 

Sorrel,  166,  243,  350,  Fig.  512. 
Sow  thistle,  435. 


Soybean,  Fig.  126. 

Spadix:  thick  or  fleshy  spike  of  certain 
plants,  (302),  Figs.  198,  251. 

Spanish  moss,  94. 

Spanish  needles,  440. 

Spathe:  bract  surrounding  or  attending 
a  spadix,  (302),  Fig.  251. 

Spatterdock,  362. 

Spatulate,  99. 

Spearmint,  402,  Fig.  543 

Species,  308. 

Specularia,  430. 

Speedwell,  408. 

Spencer,  quoted,  240. 

Spermaphytes,  183. 

Spermatozoids,  197. 

Sperm-cell,  187. 

Sphagnum  moss,  210,  Fig.  374. 

Spider-lily,  301. 

Spiderwort,  264,  266,  335,  Fig.  438; 
family,  334. 

Spike:  compact,  more  or  less  simple,  in- 
determinate cluster,  with  flowers  ses- 
sile or  nearly  so,  (250),  Figs.  185,  186, 
197. 

Spikelet:  a  secondary  spike;  one  of  a 
compound  spike,  (306). 

Spikenard,  false,  333. 

Spines,  108,  109,  Fig.  168. 

Spiranthes,  341. 

Spirea,  392;  inflorescence,  121,  Fig.  193. 

Spirogyra,  185,  186,  201,  263,  265,  Figs. 
340,  341. 

Spleenwort,  323. 

Sporangia,  186;  of  ferns,  179;  stamens, 
129. 

Sporangiophore,  188. 

Spore:  a  simple  reproductive  body,  usu- 
ally composed  of  a  single  detached  cell 
containing  no  embryo,  5,  92,  (344), 
187. 

Spore-case,  179. 

Sporodinia,  189. 

Sporogonium,  195. 

Sporophyll,  183. 

Sporophyte,  181,  201. 

Spring  beauty,  371. 

Spruce,  14,  15,  64,  98,  232,  325,  Fig.  483; 
and  light,  44;  leaf,  102. 

Spruce,  162;  cone,  Fig.  298;  seed,  Fig.  297. 

Spurge,  110,  352;  family,  351. 

Squash,  251,  289;  fruit,  162,  Fig.  296; 
germination,  171,  178;  cell,  264,  265; 
leaf,  100;  prickles,  109;  root-pressure,  74. 

Squaw-vine,  427. 

Squirrel  corn,  364. 

Stamen:  pollen-bearin  organ,  (270),  Figs. 
206,  209. 

Staminate:  having  stamens  and  no  pis- 
tils, (274),  Figs.  228-230. 

Stard,  dissecting  132,  Fig.  217. 


INDEX    AND    GLOSSARY 


463 


Stand  for  Ions,  132,  Fig.  214. 

Strfphylea,  378. 

Starch,  271;  and  sugar,  246;  aa  plant- 
food,  64;  discussed,  273,  Fig.  444;  how 
made,  78,  85;  storage  of,  31. 

Star-grass,  337. 

Star  of  Bethlehem,  331. 

Star-thistle,  441. 

Stellaria,  355,  Fig.  516. 

Stellate,  263,  298. 

Stem:  how  elongates,  16;  growth,  Figs. 
25,  26;  system,  13,  Fig.  17;  tubers,  32. 

Stemless  plants,  14. 

Sterile  flower:  no  stamens  or  pistils,  (274). 

Steven,  quoted,  303. 

Stick-seed,  413. 

Stick-tight,  169,  243,  413,  Fig.  418. 

Stigma:  part  of  the  pistil  which  receives 
the  pollen,  (272),  Fig.  209. 

Stipel:*stipule  of  a  leaflet,  (208). 

Stipule:  a  certain  basal  appendage  of  a 
leaf,  (206). 

St.  John's  wort,  130,  371,  Figs.  208,  278; 
family,  370. 

St.  Peter's  wreath,  392. 

Stock,  366. 

Stock:  the  part  on  which  the  cion  is 
grafted,  (70). 

Stolon:  a  shoot  which  bends  to  the 
ground  and  takes  root,  (56). 

Stoma,  301.  Stomate,  79,  83,  88,  192, 
298,  301. 

Stone  fruit,  161. 

Strawberry,  15,  20,  232,  249,  251,  387, 
Figs.  533,  534;  fruit,  160,  161,  Fig. 
291. 

Straw  lily,  332. 

Strict  stem  system,  15. 

Struggle  for  existence,  52,  218. 

Strychnin,  271. 

Style:  elongated  part  of  the  pistil  be- 
tween the  ovary  and  stigma,  (272), 
Fig.  209. 

Stylophorum,  363. 

Suberin,  266. 

Subterranean  stem,  15;  propagation  by, 
18. 

Suckers,  54;  of  fungi,  91. 

Sugar,  270;  cane,  250,  273,  Fig.  428. 

Sulfur,  76. 

Sumac,  300;  poison,  248,  Fig.  422. 

Summer-spore,  190. 

Sundrops,  396. 

Sunflower,  3,  19,  233,  267,  439,  Figs.  3,  4, 
23,  28;  family,  431;  inflorescence, 
120,  150,  151.  153,  Fig.  188;  trans- 
piration in,  79. 

Sunlight  and  plants,  42,  88,  223. 

Supernumerary  buds:  more  than  one  in 
an  axil,  (88). 

Survival  of  the  fittest,  240. 


Swarm-spore,  186. 

Sweet  alyssum,  160,  368,  Fig.  519. 

Sunt  briar,  390. 

Sweet  Cicely,  399. 

Sweet  clover,   243,   251,   383,   Figs.    184, 

528. 
Sweet  potato,  16,  32,  412,  Fig.  204. 
Sweet  sultan,  442. 
Sweet  William,  353,  Fig.  515. 
Swelling,  92. 

Sycamore,  294;  leaf-scar,  Fig.  474. 
Symbiosis,  193. 
Symplocarpus,  327. 
Sympode,    117,    Fig.    180.      Sympodial: 

axial   growth  continued  by  successive 

lateral  shoots,  117. 
Syngenesious:  anthers  united  in  a  ring, 

(304). 
Syringa,  395,  420. 

Table  for  laboratory  work,  Fig.  477: 

Tabular,  263. 

Tamarack,  326. 

Tanacetum,  439. 

Tangle-berry,  424. 

Tannin,  271. 

Tansy,  439. 

Tap-root,  7,  Fig.  8. 

Taraxacum,  434. 

Tare,  381. 

Tea  plant,  Fig.  90. 

Teasel,  3,  244. 

Tecoma,  capsule,  Fig.  285. 

Teleutospore,  191. 

Tendrils,   climbers,   112,   113,  Figs.   175- 

177;  roots  as,  10;  as  leaves,  105. 
Terminal  bud,  37,  50,  Figs.  58-87. 
Terminal  flowers,  119,  Fig.  181. 
Terrestrial,  207. 
Teucrium,  402. 
Thalictrum,  357. 
Thallophyte,  183,  185. 
Thallus,  18.5. 

Thinning,  258,  Figs.  432,  433. 
Thistle,    150,    169,   243,   441,    Figs.    253- 

255;  Canada,  19,  22,  242,  244,  441,  Fig. 

409;  Russian,  170,  243,  Fig.  114;  seed, 

168;  inflorescence,  120. 
Thorns,  108,  Figs.  164,  167. 
Thoroughwort,  444. 
Thuja,  326,  Fig.  4S5. 
Thyrse:    compound    cluster    with    main 

axis  indeterminate  and  branches  deter- 

minate,  (259). 
Tiarella,  393. 
Tickseed,  440. 

Tiers  of  branches,  56,  Figs.  93,  94. 
Tiger  lily.  21,  33,  Fig.  31. 
Tillandsia,  94. 
Timber  crop,  249,  256. 
Tissues,  278. 


464 


INDEX    AND    GLOSSARY 


Toad-flax,    19,    22,    244,    405,    Fig.    544; 

flower,  145;  fruit,  Fig.  281;  pollination, 

137,  Fig.  227. 
Toadstools,  187. 
Tobacco,  251,  271,  411. 
Tomato,    4,    75,    251,    410;    fruit,    160; 

-potato  graft,  28. 
Tooth-wort,  366,  Fig.  266. 
Torus:  part  or  organ  to  which  the  parts 

of  the  flower  are  attached;  upper  end  of 

the  flower-stalk,  (268). 
Touch-me-not,  166,  375,  Fig.  449. 
Toxylon,  347,  Fig.  510. 
Tracheids,  281. 
Tradescantia,    264,    265,    266,    276,    335, 

Fig.  43S;  stomates,  299. 
Tragopogon,  434. 
Trailing  stems,  14,  Fig.  18. 
Transpiration:  giving  off  of  water,   (157, 

166),  Figs.  128,  129. 
Trees:    plants    that    produce    one    main 

trunk    and    an    elevated    head,     (15); 

and  wind,  213,  Figs.  379-381;  forms  of, 

64,  Figs.  111-113,  116-119;  roots,  7. 
Trifolium,  382,  Fig.  527. 
Trillium,  145,  233,  332,  Fig.  244. 
Trimerous:  in  3's,  (291). 
TropKolum,  374. 
Trumpet-creeper,  10,   113,   160,  Figs.   12, 

285. 
Truncate:  squared   as  if  cut   off,    (211), 

Fig.  154. 
Trunk,  form  of,  65. 
Tsuga,  326,  Fig.  484. 
Tuber:  short  congested  part,  (78). 
Tuberose,  337. 
Tulip,  330. 

Tulip-tree,  leaf,  Fig.  154;  seed,  168. 
Tumble-grass,  170. 
Tumble-weeds,  170. 
Tunicated  bulb,  33. 
Turnip,    33,    251,    Fig.    47;    fruit,    160; 

root-hairs,  12;  starch  in,  31. 
Turtlehead,  406. 
Tussilago,  442. 
Twiners,  112,  115. 
Twin-leaf,  360. 
Type,  236. 

Ulmus,  346,  Figs.  507-509. 

Umbel:  corymbose  cluster  with  branches 

of  about  equal  length  and  arising  from 

a  common  point,  (255). 
Umbellet:  secondary  umbel,  (255), 
Umbelliferse,  121,  122,  247,  397. 
Uncinula,  189. 
Undergrowth,  232. 
Undulate:  wavy,  (212). 
Uredospore,  192. 
Urtica,  348. 
Urticacete,  345. 


Utricularia,  71,  207. 

Uvularia,  332.  • 

Vaccinium,  424. 

Vacuole,  264. 

Valves:  separable  parts  of  a  pod,   (312)= 

Variation,  236. 

Variety,  236. 

Vascular,  263,  278,  282. 

Vase-form  trees,  64,  Fig.  112. 

Vaucheria,  186,  187,  263,  Figs.  342,  343. 

Velum,  201. 

Velvet  leaf,  373. 

Venation:  veining,  (203). 

Venus'  looking-glass,  430. 

Verbascum,  298,  405. 

Verbena,  403;  cutting,  25,  Fig.  37. 

Verbenaceae,  403. 

Vernonia,  445. 

Veronica,  408. 

Verticillate:  with  three  or  more  leaves  or 

flowers  at  one  node,  (113). 
Vervain,  403;  family,  403. 
Vetch,  251,  381;  nodules  on  root,  78. 
Vetchling,  381. 
Viburnum,  429. 
Vicia,  381. 
Vigna,  384,  Fig.  532. 
Vinca,  419. 
Violaceas,  369. 
Violet,   3,   233,   249,   369;  cleistogamous, 

140,  Fig.  236;  seeds,  166;  family,  369. 
Viper's  bugloss,  415. 
Virginia  creeper,   tendril,    113,    114,   117, 

Fig.  175. 
Virgin's  bower,  359. 

Wahoo,  294. 

Wake-robin,  332. 

Wallflower,  fruit,  160;  hairs,  298. 

V/alnut,  155;  buds,  37,  138;  inflorescence, 

121,  Fig.  190. 
Wandering  Jew,  335. 
Water  arum,  328. 
Water  cress,  367. 
Water  hoarhound,  400. 
Waterleaf,  415;  family,  415. 
Water-lily,  3,  98,  205,  207,  361;   family, 

361;    and    mineral    nutrients,    69,    75; 

fungi,  266. 
Watermelon,  251. 
Watersprout,  54. 
Wax-work,  twiner,  115. 
Weeds,  220,  230,  241. 
Weigela,  61,  429. 
Wheat,  77,  152,  221,  242,  249,  250,  254; 

field,  68,  225,  Fig.  384;  flower,  151,  Fig. 

259;  germination,  173;  inclusions,  276, 

Fig.  445;  India,  350;  starch,  274,  275; 

roots,  7;  rust,  189,  190,  Figs.  352-357. 
Whiteweed,  150,  242,  438,  Fig.  189. 


INDEX     AND     GLOSSARY 


465 


Whorl:  three  or  more  leaves  or  flowers 
at  one  node,  (113). 

Wild  geranium,  Fig.  19.r>. 

Wild  .Kits,  332. 

Willow:  buds,  39,  Figs.  60,  91;  outting3, 
21,  26;  dioecious,  138;  expression  in, 
66;  inflqreseence,  117,  Fig.  229;  leaf, 
99,  Fig.  145;  mildew,  189,  Figs.  348- 
351;  phyllotaxy,  48;  pussies,  121,  Fig. 
60;  seeds,  168. 

Willow-herb,  394. 

Wilting,  80. 

Wind  and  plants,  138,  213. 

Windflower,  356. 

Winter  bud,  36.  50,  61. 

Winter-cress,  366. 

Wintergreen,  424,  Fig.  22;  anther,  135; 
fringed,  140. 


Wistaria,  115,  380. 
Witch-hazel,  166. 
Wood-sorrel,  166,  374. 
Wood  tissue,  281. 
Woody  structure,  3. 

Xant liium,  436,  Fig.  555. 
Xerophytic  society,  228. 
Xylem,  283. 
Xylol,  302,  303. 

Yarrow,  437. 
Yeast,  263. 
Yew,  fruit,  164. 

Zebrina,  335. 

Zone  societies,  233,  Fig.  403. 

Zygospore,  186. 


of 


a*0s** 


PRACTICAL  PHYSICS  FOR 
SECONDARY  SCHOOLS 

By  N.  HENRY  BLACK,  of  the  Roxbury   Latin  School.  Bo8ton.  and 
Prof.  HARVEY   N.  DAVIS,  of  Harvard    University 

Cloth,    l2mo.,    illustrated,  488  pages,    list  price,    $1 .25 


"In  preparing  this  book,"  say  the  authors  in  the  Preface,  "we  have  tried 
to  select  only  those  topics  which  are  of  vital  interest  to  young  people, 
whether  or  not  they  intend  to  continue  the  study  of  physics  in  a  col- 
lege course. 

"In  particular,  we  believe  that  the  chief  value  of  the  informational 
side  of  such  a  course  lies  in  its  applications  to  the  machinery  of  daily  life. 
Everybody  needs  to  know  something  about  the  working  of  electrical 
machinery,  optical  instruments,  ships,  automobiles,  and  all  those  labor- 
saving  devices,  such  as  vacuum  cleaners,  tireless  cookers,  pressure  cookers, 
and  electric  irons,  which  are  found  in  many  American  homes.  We  have, 
therefore,  drawn  as  much  of  our  illustrative  material  as  possible  from 
the  common  devices  in  modern  life.  We  see  no  reason  why  this  should 
detract  in  the  least  from  the  educational  value  of  the  study  of  physics, 
for  one  can  learn  to  think  straight  just  as  well  by  thinking  about  an 
electrical  generator,  as  by  thinking  about  a  Geissler  tube 

"To  understand  any  machine  clearly,  the  student  must  have  clearly 
in  mind  the  fundamental  principles  involved.  Therefore,  although  we 
have  tried  to  begin  each  new  topic,  however  short,  with  some  concrete 
illustration  familiar  to  young  people,  we  have  proceeded,  as  rapidly  as 
seemed  wise,  to  a  deduction  of  the  general  principle.  Then,  to  show  how 
to  make  use  of  this  principle,  we  have  discussed  other  practical  applica- 
tions. We  have  tried  to  emphasize  still  further  the  value  of  principles, 
that  is,  generalizations,  in  science,  by  summarizing  at  the  end  of  each 
chapter  the  principles  discussed  in  that  chapter.  In  these  summaries 
we  have  aimed  to  make  the  phrasing  brief  and  vivid  so  that  it  may  be 
easily  remembered  and  easily  used." 

The  new  and  noteworthy  features  of  the  hook  are  the  admirable 
selection  of  familiar  material  used  to  develop  and  apply  the  principles 
of  physical  science,  the  exceptionally  clear  and  forceful  exposition, 
showing  the  hand  of  the  master  teacher,  the  practical,  interesting, 
thought-provoking  problems  and  the  superior  illustrations. 


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CHEMISTRY  AND  ITS 
RELATIONS  TO  DAILY  LIFE 

By  LOUIS  KAHLENBERG  and  EDWIN  B.  HART 

Professors  of  Chemistry  in  the  University  of  Wisconsin 
Cloth,    l2mo.,  illustrated,  393  pages,   list  price,  $1.25 


If  the  contributions  of  chemical  science  to  modern  civilization 
were  suddenly  swept  away,  what  a  blank  there  would  be!  If,  on  the 
other  hand,  every  person  were  acquainted  with  the  elements  of 
chemistry  and  its  bearing  upon  our  daily  life,  what  an  uplift  human 
efficiency  would  receive!  It  is  to  further  this  latter  end  that  this 
book  has  been  prepared.  Designed  particularly  for  use  by  students 
of  agriculture  and  home  economics  in  secondary  schools,  its  use  will 
do  much  to  increase  the  efficiency  of  the  farm  and  the  home.  In  the 
language  of  modern  educational  philosophy,  it  "functions  in  the  life 
of  the  pupil." 

Useful  facts  rather  than  mere  theory  have  been  emphasized 
although  the  theory  has  not  been  neglected.  The  practical  character 
of  the  work  is  indicated  by  the  following  selected  chapter  headings: 

II.  The  Composition  and  Uses  of  Water. 

IV.  The  Air,  Nitrogen,  Nitric  Acid  and  Ammonia. 

IX.  Carbon  and  Its  Compounds. 

XII.  Paints,  Oils  and  Varnishes. 

XIII.  Leather,  Silk,  Wool,  Cotton  and  Rubber. 

XV.  Commercial  Fertilizers. 

XVI.  Farm  Manure. 

XX.  Milk  and  Its  Products. 

XXI.  Poisons  for  Farm  and  Orchard  Pests. 


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Warren's  Elements  of  Agriculture 

By  G.  F.  WARREN,  Professor  of  Farm  Management  and 
Farm  Crops,  New  York  State  College  of  Agriculture  at  Cor- 
nell University 

Cloth,  /jmo,  456  pages,  $1.10  net 

Written  by  Professor  G.  F.  Warren,  who  is  in  charge  of  the  Department  of 
Farm  Management  and  Farm  Crops  in  the  New  York  State  College  of  Agri- 
culture, Cornell  University,  an  authority  on  questions  pertaining  to  practical 
agriculture. 

Professor  Warren  is,  moreover,  a  farmer.  He  grew  up  on  a  farm  in  the  mid- 
dle West  and  is  living  at  the  present  time  on  a  farm  of  three  hundred  and 
eighteen  acres,  which  he  supervises  in  connection  with  his  work  at  the  Univer- 
sity. 

The  "  Elements  of  Agriculture  "  is  a  text  that  does  not  "  talk  down  "  to  the 
pupil.  It  gives  agriculture  rank  beside  physics,  mathematics,  and  the  languages, 
as  a  dignified  subject  for  the  course  of  study. 

In  Warren's  "  Elements  of  Agriculture  "  there  is  no  waste  space.  It  is  writ- 
ten with  the  ease  that  characterizes  a  writer  at  home  in  his  subject,  and  it  is 
written  in  a  style  pedagogically  correct.  The  author  has  been  a  teacher  of  high 
school  boys  and  girls  and  knows  how  to  present  his  subject  to  them. 

Experts  in  the  teaching  of  agriculture  the  country  over  have  been  unanimous 
in  praise  of  the  text.     For  instance: 

Mr.  J.  E.  Blair,  Supt.  of  Schools,  Corsicana,  Texas  : 

"  An  examination  of  Warren's  '  Elements  of  Agriculture  '  convinces  me  that 
it  is  a  book  of  uncommon  merit  for  secondary  schools  as  well  as  for  the  private 
Student.  It  is  thoroughly  scientific  in  matter,  and  is  written  in  an  attractive 
style,  that  cannot  fail  to  please  as  well  as  instruct." 

Supt.  E.  S.  SMITH,  Whiting,  Iowa  : 

"  I  am  very  much  pleased  with  Warren's  '  Elements  of  Agriculture.'  In  my 
opinion  it  is  the  only  book  on  the  market  that  presents  tin?  work  of  agriculture 
suitably  for  high  schools ;  too  many  books  are  too  simple  and  do  not  give 
enough  work;  a  book  for  high  schools  must  be  more  than  a  primer." 


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New  Physical  Geography 

By   RALPH    S.    TARR 

Late  Professor  of  Physical  Geography  in  Cornell  University 

Cloth,  i2tno,  fully  illustrated,  pp.  457.     $1.00  net 
Some  points  of  interest  in  connection  with  this  book  are  : 

1.  The   author   has  an   international    reputation  as   an 

authority  in  the  field  of  geology  and  physical 
geography. 

2.  In  both  content  and  method  of  presentation  the  book 

makes  a  strong  appeal  to  the  human  interest  of 
the  pupil.     It  is  well  written. 

3.  It  gives  particular  attention  to  the  geography  of  the 

United  States. 

4.  The  illustrations  are  numerous,  superior  in  quality, 

and  significant,  and  they  are  used  systematically 
throughout  the  book. 

5.  Topic  summaries,  topical  outlines,  and  review  ques- 

tions following  each  chapter  make  its  use  easy  for 
both  pupil  and  teacher. 

6.  Experience   shows   that  it   possesses  to  an   unusual 

degree  those  qualities  that  make  a  book  a  success 
in  the  classroom.  It  is  widely  used  with  great 
satisfaction. 


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